####018007697#### FXUS62 KTAE 040535 AFDTAE Area Forecast Discussion National Weather Service Tallahassee FL 135 AM EDT Sat May 4 2024 ...New AVIATION... .UPDATE... Issued at 913 PM EDT Fri May 3 2024 Main updates were to refine rain chances through the overnight hours and into early parts of Saturday morning. Upper level shortwave pivots through in the overnight hours and with upstream activity still continuing and some weak low-level convergence this evening along a frontal boundary, I have upped rain chances slightly for the overnight hours. Much of the activity the next few hours will be across southeast AL as the shortwave pivots through, with lighter showers elsewhere. This activity slides east overnight and then more activity develops closer to daybreak across the I-75 corridor and into the eastern Big Bend as the upper level forcing and weak frontal boundary help spur new development. && .NEAR TERM... (Through Saturday) Issued at 248 PM EDT Fri May 3 2024 Vapor imagery this afternoon depicts a storm system attendant to its shortwave trough traversing eastward across the Lower MS Valley with a downstream ridge axis bisecting the Coastal Carolinas down to the FL Peninsula. These features are making for warm/moist conditions with a mix of cloudiness, and isolated showers & thunderstorms today. The latter is seabreeze driven, initially focused mostly along the Eastern FL Big Bend before drifting towards the I-75 corridor into the early evening hrs. Additional cell development is possible from remnant outflow boundaries during that time. Lingering showers are possible tonight from the west as the aforementioned shortwave pivots NE through the Wiregrass. A muggy airmass will make for an unseasonably warm overnight/early-morning period with widespread forecast lows in the upper 60s, or about 10- 12 degrees above normal! Patchy fog is also forecast to develop in the pre-dawn hrs from Southern AL/Emerald Coast, then spreading to the FL Big Bend into parts of South-Central GA. Dissipation should occur within a couple hrs after sunrise. For tomorrow, expect greater coverage of showers and thunderstorms thanks to some upper-level support provided by the lifting shortwave, afternoon seabreeze, and sufficient daytime instability amidst a moist airmass. These parameters should support deep convection capable of strong/gusty winds, frequent lightning, and locally heavy downpours. The latter could produce localized high rain amounts exceeding 1 inch. Minimal vertical wind shear precludes severe weather concerns, but several strong storms (perhaps isolated "pulse" severe) are likely. The best chances are along the interstate corridors, followed by a northward drift past the FL state line. Aside from storm activity, temperatures peak in the mid/upper 80s. && .SHORT TERM... (Saturday night through Sunday night) Issued at 248 PM EDT Fri May 3 2024 Another shortwave will move across the mid-South Sunday into Sunday evening, which will bring another enhancement to our chances for showers and storms Sunday afternoon. The highest rain chances will be across southwest GA and the eastern FL Big Bend. Some mid-level dry air as well as inverted-V profiles on forecast soundings may lead to some gusty wind potential Sunday afternoon. Otherwise, it will continue to be warm and humid with highs in the upper 80s and lows in the mid to upper 60s. && .LONG TERM... (Monday through Thursday) Issued at 248 PM EDT Fri May 3 2024 One more shortwave traverses the Tennessee and Ohio Valleys Monday afternoon, which provides another boost to our rain chances. However, forecast soundings don't appear as conducive for gusty winds given less mid-level dry air and more moisture near the surface. Highs Monday will be in the upper 80s with lows in the mid to upper 60s. Beyond Monday, strong ridging takes hold of the area, shutting off the rain and bringing increasing heat through the middle to latter part of the week. Ensemble guidance indicates that we may see 500 mb heights near 589-590 dam, which is close to record heights for this time of year based on SPC's sounding climatology. Similarly, 850 mb temperatures will be in the 18-22C range, which is also near record levels for this time of year. All that to say, it's going to be hot. Highs will climb in to the lower to middle 90s, and with dew points near 70, heat index values could approach 100 in some areas. Lows will also climb into the upper 60s to lower 70s. && .AVIATION... (06Z TAFS) Issued at 133 AM EDT Sat May 4 2024 Fog and/or low stratus will be possible across most of the area this morning with light showers also possible across the northern sites. Conditions should improve to VFR by mid to late morning. Scattered to widespread showers and storms are expected this afternoon, with the best chances across TLH/ABY/VLD. && .MARINE... Issued at 351 AM EDT Fri May 3 2024 High pressure in the Atlantic will lead to tranquil boating conditions through the period. Light winds, generally out of the south-southeast, are expected with seas around 1 to 3 feet into the weekend. There is a slight chance of showers and thunderstorms Saturday and Sunday. && .FIRE WEATHER... Issued at 248 PM EDT Fri May 3 2024 Afternoon and early evening thunderstorms capable of gusty/erratic winds and lightning will be the main fire concerns the next 3 days. For tomorrow, convection aims to focus along the interstate corridors after seabreeze initiation on the Big Bend side, then drifting north past the FL state line. Convective potential is expected to be greater compared to today. Wetting rains are also possible. Additional rounds of diurnal showers/thunderstorms are forecast Sunday-Monday, albeit lesser coverage, but targeting roughly the same locations as Saturday. Otherwise, look for hot daytime conditions with highs in the upper 80s away from the immediate coast, southerly winds, and a daily afternoon seabreeze. High dispersions are forecast over parts of SE AL/FL Panhandle Monday afternoon. && .HYDROLOGY... Issued at 248 PM EDT Fri May 3 2024 Abundant moisture will be in place with a decent coverage of showers and storms this weekend. While widespread totals of 0.5 to 1 inch, localized totals if storms are slow moving could reach 2 to 3 inches in a short period of time. This could result in some nuisance flooding of poor drainage or urban areas. Otherwise, no additional flood concerns are expected. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 86 67 88 67 / 70 10 40 0 Panama City 83 67 85 68 / 20 0 10 0 Dothan 89 65 88 66 / 40 10 40 0 Albany 87 67 88 68 / 70 30 50 20 Valdosta 86 67 88 67 / 70 30 60 20 Cross City 87 66 88 65 / 50 20 50 10 Apalachicola 80 69 82 70 / 20 0 10 0 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ NEAR TERM...IG3 SHORT TERM...Young LONG TERM....Young AVIATION...Merrifield MARINE...Reese FIRE WEATHER...IG3 HYDROLOGY...Young ####018006953#### FXUS63 KJKL 040536 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 136 AM EDT Sat May 4 2024 .KEY MESSAGES... - Shower and thunderstorm potential returns to the forecast through the next 7 days. - Cooler than in recent days, but temperatures are forecast to be above normal through the next 7 days. && .UPDATE... Issued at 1150 PM EDT FRI MAY 3 2024 Scattered showers are found through eastern Kentucky along with a potential for a stray thunderstorm. Have updated the forecast mainly to fine tune the PoPs and thunder chances through the rest of the night per radar and CAMs trends. Did also include the latest obs and tendencies for the T/Td grids. These adjustments have been sent to the NDFD and web servers along with a freshening of the zones and SAFs. UPDATE Issued at 745 PM EDT FRI MAY 3 2024 23Z sfc analysis shows low pressure having moved a little closer to the area from the west and this has pushed the protective area of high pressure out of Kentucky. Accordingly, return flow moisture has helped fuel showers across the region today along with a few thunderstorms. Currently, the best batch of convection is west of the I-75 corridor. This is expected to drift east with time - but weaken. The extra clouds around today along with the showers have kept temperatures on the cooler side compared to yesterday. The latest obs have temperatures generally in the upper 60s to lower 70s. Meanwhile, amid light and variable winds, dewpoints have moistened into the low to mid 60s for most spots. Have updated the forecast mainly to fine tune the PoPs and thunder chances through the night per radar and CAMs trends. Did also add in the latest obs and tendencies for the T/Td/Sky grids. These adjustments have been sent to the NDFD and web servers along with a freshening of the zones, SAFs, and HWO. && .SHORT TERM...(This evening through Saturday night) Issued at 332 PM EDT FRI MAY 3 2024 An active pattern remains across the Bluegrass State through the short term. Large upper low/trough configuration remains over the far northern US and south-central Canada with an active jet stream from the Central Plains to Upper Great Lakes region. Meanwhile, upper ridging remains persistent along the East Coast, and will begin to move offshore Saturday night as the aforementioned upper low begins to move northeast toward eastern Canada at that time. This leaves eastern Kentucky under the influence of a moist and active regime with periodic shortwave disturbances moving across the region through Saturday evening. Currently a disturbance is beginning to exit to the east this afternoon, but will be followed by another tonight into Saturday morning that will bring another round of showers and possibly a few thunderstorms. Models suggest low-level instability is somewhat lacking but there is sufficient elevated instability to warrant a few claps of thunder from time to time, especially west of I-75. Fog formation overnight will be dependent on any lulls in precipitation as well as any potential partial clearing. Lows tonight will range from the mid-50s in the cooler sheltered valleys to lower 60s elsewhere. Another disturbance appears to be well-timed with any daytime heating to help produce more widespread showers and thunderstorms Saturday. Given high PoPs and cloud cover through the day temperatures will struggle to reach the current forecast highs of upper 70s. PoPs gradually lower through Saturday evening through the overnight as a trailing shortwave crosses the area with shortwave ridging building in from the southwest after midnight. Sky cover will likely trend downward but this would likely then promote fairly widespread fog formation late Saturday night into Sunday morning, especially in the river valleys. Expect forecast lows Saturday night similar to tonight's forecast, with mid 50s to lower 60s. .LONG TERM...(Sunday through Friday) Issued at 540 PM EDT FRI MAY 3 2024 The models generally agree on a fairly stagnant long wave pattern across the CONUS through the majority of next week. A seasonably strong 500 mb low pressure system will start out over the West Coast early Sunday morning, before swinging east, residing over the northern Rockies/northern High Plains by early Tuesday. This feature will then elongate and gradually dampen with time as it moves over the Upper Midwest, with a broad positively tilted trough aligning from the Great Lakes back through the Desert Southwest. This will keep west to west southwest flow across the Ohio and Tennessee valleys aloft, with several progressive short wave troughs to move through the region at times. At the surface, a quasi-stationary front will be aligned just north of the area through early next week, before a cold front approaches by the end of the next work week. This will all result in unsettled weather across eastern Kentucky through the long term forecast, with daily chances of showers and thunderstorms. Have generally stayed a bit below the blended guidance on PoPs for the days where the overall forcing is weaker and/or less certain, as it is known to overdo more diurnally influenced convection. At this time, rain chances look to peak on Monday (80-90%), and then again on Thursday (70-80%), with better forcing at play. The rest of the period will feature chance PoPs (30-60%). Temperatures will average 5-10 degrees above normal, with lows mainly in the lower 60s, while highs range from the upper 70s to lower 80s most days. && .AVIATION...(For the 06Z TAFS through 06Z Saturday night) ISSUED AT 135 AM EDT SAT MAY 4 2024 Scattered showers, and perhaps an isolated thunderstorm, will continue across the area through the night. The challenge will be determining whether or not a particular TAF site sees any showers or storms, so VCTS or VCSH were used to account for any such activity. We should see an uptick in showers and storms after the sun comes up, as heating begins to occur and instability increases. This will be especially true during the early afternoon through early evening hours on Saturday. In fact, widespread showers and at least scattered storms are expected from around 17Z today through around 2Z Saturday night. MVFR to IFR CIGs will be possible with any storm or intense shower, along with brief periods of MVFR VSBYs. Winds should be out of the south or southwest at less than 10kts during the day, but could be stronger and gusty with any storms that affect at TAF site. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...CMC LONG TERM...GEOGERIAN AVIATION...AR ####018006620#### FXUS64 KLZK 040537 AFDLZK Area Forecast Discussion National Weather Service Little Rock AR 1237 AM CDT Sat May 4 2024 ...New AVIATION... .SHORT TERM... (This evening through Sunday) Issued at 145 PM CDT Fri May 3 2024 Currently, showers and thunderstorms have since weakened and/or pushed out of the CWA. Rain chances still prevail across portions of eastern and southeastern Arkansas. CAMs shows the possibility of additional pop-up showers and thunderstorms over portions of southern and northern Arkansas later this afternoon. Coverage is expected to be spotty and should dissipate shortly after sunset. The pattern is expected to remain somewhat unsettled through the short term as weak disturbances push through the state. The next best chance of rain and thunderstorms will return Saturday afternoon as a weak shortwave moves across the state bringing the possibility of afternoon thunderstorms. The threat for severe weather appears to remain low at this time. Sunday brings a better chance of widespread rain across the state as another disturbance moves through. Rain is likely across western locations Sunday morning pushing from southwest to northeast across the state through Sunday evening. Once again, severe weather is expected to remain on the low end...however, gusty winds and small hail cannot be ruled out with these storms. Overall, QPF could be up to a half an inch across much of the state with some areas possibly seeing between one to two inches depending where the strongest storms pop-up. Temperatures are expected to be warmest on Saturday with highs in the mid 70s to mid 80s. High temperatures on Sunday are expected to drop into the 70s. Overnight low temperatures are expected to be in the low to mid 60s through the period. && .LONG TERM... (Sunday Night through next Friday) Issued at 145 PM CDT Fri May 3 2024 SUNDAY NIGHT/MONDAY/TUESDAY/WEDNESDAY: An unsettled weather pattern takes hold into the day on Monday and will remain in place for much of the long-term forecast period. On Monday an upper lvl negatively tilted trof axis approaches the Central Plains region of the CONUS in conjunction with a sfc low pressure center positioned across the Northern Plains region of the CONUS with an attendant southward extending cold front and dryline that will initiate storms on Monday. A parameter space of strong southerly sfc flow which will advect warm air temperatures and appreciable dewpoint temperatures into the state setting the table for the possibility of severe weather across much of the state will take place. The SPC (Storm Prediction Center) has already outlined a slight risk for severe weather across portions of the CWA with possible upgrades to come in future outlooks closer to Tuesday. Expect the possibility of all modes of severe weather to be possible on Tuesday. It will become clearer in future forecast packages/discussion exactly what the main weather hazards will be, but the parameter space across the CWA will be primed for all hazards of severe weather. Into Tuesday, an upper lvl closed low positions over the Northern Plains region of the CONUS with a pronounced southern stream of which will include a 70 to 80 knot jet axis will be present over the state. At the sfc, the same parameter space will exist from Monday with the addition of upper lvl dynamics in place and closer sfc lvl features including: a localized low pressure center across Oklahoma and attendant southward extending dryline with a cold front approaching from the northwest as a result from the parent sfc low pressure center fixated across the Northern Plains region of the CONUS. Again, the SPC (Storm Prediction Center), on Wednesday has outlined a slight risk for severe weather which includes a large portion of the state of Arkansas. Expect a second round of severe weather on Wednesday, with this severe weather threat looking to be a larger area that includes most of the CWA. Expect the possibility of all modes of severe weather to be possible on Wednesday. It will become clearer in future forecast packages/discussion exactly what the main weather hazards will be, but the region across the CWA and most of the state will be suspect to all hazards of severe weather. THURSDAY/NEXT FRIDAY: A series of multiple Sits move over Arkansas during this period in tandem with a cold front that begins to move across the state on Thursday into Next Friday. Expect several rounds of rain and thunderstorms over this three day period of unsettled weather. It remains to be determined if the ingredients will be in place to pose a threat for severe weather. Over the period in terms of temperatures, with respect to both low and high temperatures will be 5 to 10 degrees above normal compared to climatological normals over the same timeframe. && .AVIATION... (06Z TAFS) Issued at 1228 AM CDT Sat May 4 2024 A couple locations were hovering near or at MVFR CIGs, otherwise most locations were VFR as of 06z. Some patchy FG/low stratus is expected to develop and impact area terminals, with conds ranging from MVFR to IFR. The next round of SHRA/TSRA will arrive from the W and NW on Sat with the passage of another weak upper level disturbance. Highest confidence in PoPs would be over Cntrl sections of the state during the afternoon time frame. This activity will push SE with time and should wind down near sunset with VFR conds returning. Winds will be light through the period. && .PRELIMINARY POINT TEMPS/POPS... Batesville AR 82 62 77 64 / 60 30 90 50 Camden AR 83 67 78 63 / 40 40 70 30 Harrison AR 76 60 70 59 / 70 30 80 40 Hot Springs AR 82 65 75 63 / 50 40 80 40 Little Rock AR 84 65 78 66 / 50 40 80 40 Monticello AR 83 66 79 66 / 40 30 70 40 Mount Ida AR 81 65 73 63 / 60 50 90 30 Mountain Home AR 79 60 73 60 / 60 30 80 40 Newport AR 83 64 80 65 / 50 30 80 60 Pine Bluff AR 83 65 78 65 / 40 30 80 40 Russellville AR 80 64 73 62 / 50 40 80 30 Searcy AR 82 64 75 63 / 50 30 80 50 Stuttgart AR 82 65 78 66 / 50 30 80 50 && .LZK WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...73 LONG TERM....74 AVIATION...70 ####018008104#### FXUS61 KBTV 040537 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 137 AM EDT Sat May 4 2024 .SYNOPSIS... Dry and seasonably warm weather will continue across the region to start the weekend, with the exception of a few possible showers across northern New York on Saturday before widespread precipitation returns for Sunday. A period of warmer and sunnier conditions are expected for the start of the week, with more unsettled weather returning by the middle of next week. && .NEAR TERM /THROUGH SUNDAY/... As of 1238 AM EDT Saturday...Southerly flow is preventing temperatures from falling quickly across the Champlain Valley and parts of northern New York so had to bump them up a little. Rain showers are trying to enter the St. Lawrence Valley but most of them have not been able to reach the ground so trimmed PoPs slightly. Clouds are slowly lowering from west to east and this should continue for the rest of the night. Overall, the forecast is mostly on track so all the edits were minor. Previous discussion follows Previous discussion...Surface high pressure and upper level ridging across the region haver made for a pleasant Friday afternoon, with dry conditions and seasonably warm temperatures. As we head into the evening, the upper level ridge axis will continue to shift eastward,although dry conditions will persist. There will be increasing high clouds across the region overnight associated with a frontal boundary to our west. Unlike the last few nights, increased clouds and winds will inhibit any fog development across the region. A light rain shower or two may be possible across northern New York early Saturday morning as the frontal boundary moves closer, but any measurable precipitation would be minimal. Overnight low temperatures will be mild, in the 40s to low 50s. Saturday will be another pleasant day as we remain under the influence of high pressure, with mostly dry weather. Temperatures will warm into the 60s to near 70 in some of the broad valley locations, with high clouds remaining overhead. Dry weather will continue through most of Saturday night, with the latest guidance continuing to trend on the drier side for Saturday night with a strong ridge axis in place. Another mild night is expected, with temperatures in the 40s to low 50s ahead of approaching widespread precipitation on Sunday. && .SHORT TERM /SUNDAY NIGHT/... As of 303 PM EDT Friday...PWATs rise to around 1.5 standard deviations above normal on Sunday as moisture with Gulf of Mexico origin looks to overspread the region. Upper level pattern shows a stout omega block shifting east of our area into Maine, increasing shower chances and coverage on Sunday. However, organized convection is not expected as the main jet energy associated with the shortwave trough moving eastward from the Great Lakes is diverted into Quebec. As a result, the main trough axis does not approach North Country until sometime next Tuesday. This will be discussed in the long term section of the forecast discussion. Indeed, forecast soundings show a lack of surface-based instability, so showers with brief locally heavy downpours look to be the main risk. While there could be embedded thunder due to elevated instability, no organized thunderstorms are anticipated. PoPs do increase to the likely category with scattered to perhaps numerous showers on Sunday. While there would likely be widespread wetting rainfall, QPF amounts are quite manageable in the 0.1 to 0.3 inch range with locally higher amounts. Indeed, the MMEFS shows none of our area rivers going into action stage. Sunday will be quite a bit cooler than Saturday, with highs only in the 50s with low 60s possible if there are breaks in the rain or clouds. In addition, a 40-50 kt 925mb southerly low level jet overspreads the region on Sunday. NAEFS situational awareness ensemble table shows the v vector wind rising to almost 2.5 standard deviations above normal, so it will be breezy if not blustery. A mitigating factor is that the waters of Lake Champlain is still quite cold with water temperatures still in the low to mid 40s, which is almost isothermal to the forecast 925mb temperatures in the +5 to +8C range. That could reduce the mixing potential in the boundary layer. So have mostly kept wind gusts in the 30 to 35 mph range across the Champlain Valley despite the southerly wind component being anomalously strong. Overall, no overall hazardous weather to speak of but Sunday does look to be a less than ideal day for outdoor activities. Heading into Sunday night, showers taper off and the boundary layer looks well mixed enough to preclude widespread fog development. Temperatures stay quite mild in the mid 40s to low 50s. && .LONG TERM /MONDAY THROUGH FRIDAY/... As of 303 PM EDT Friday...The overall weather pattern heading into the first full week of May can be described as unsettled with no real significant warm up or impactful weather. Unsurprisingly, the CPC 8-14 day temperature outlook favors near normal temperatures and leans towards above normal rainfall. For reference, typical highs for North Country in early May are in the low to mid 60s, while average overnight lows are in the mid 30s to low 40s. The upper level pattern features a positively tilted omega block sandwiched between an anomalously deep trough across the Rockies/northern Great Plains and another trough over eastern Quebec/Newfoundland. H5 height anomalies favor a period of widespread showers and thunderstorms in the Tuesday/Wednesday time frame, as positive H5 height anomalies give way to near normal values. Depending on the timing of the associated surface cold front, ingredients may exist for a few stronger storms. Taking a first look at ensemble guidance probabilities, it does look like the better chance for organized convection is across our southwestern zones, with more garden variety thunderstorms towards Vermont and the Champlain Valley. This makes sense from a synoptic perspective as the aforementioned positively tilted omega block may not be that easy to dislodge. As a result, our region only gets a piece of weak shortwave energy that peels off from the base of the northern Great Plains upper low and deamplifies as it tracks towards southern Ontario/Quebec. In simple terms, our region gets a glancing blow in terms of dynamical forcing and as a result, the odds for any stronger convective storms greatly diminish. While we are still 4 days away, model trends are favoring an unsettled but benign pattern for North Country in the upcoming week. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Through 06Z Sunday...VFR conditions should persist through the entire TAF period though moist southeast flow could cause ceilings at MPV to lower to MVFR Saturday night. A few light showers are possible tonight at MSS and SLK but they will not be heavy enough to cause any visibility concerns. Wind shear has either met LLWS criteria or is very close to meeting it at all the terminals. The wind shear should continue for the rest of the night before lowering during the day. Winds will be relatively consistent through the entire TAF period, generally light from the southeast though MSS should be light out of the northeast. Outlook... Sunday: Mainly MVFR, with areas VFR possible. Definite SHRA. Sunday Night: Mainly MVFR, with areas IFR possible. Chance SHRA. Monday: Mainly VFR, with local IFR possible. Slight chance SHRA. Monday Night: VFR. NO SIG WX. Tuesday: VFR. NO SIG WX. Tuesday Night: VFR. Slight chance SHRA. Wednesday: VFR. Likely SHRA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Kremer NEAR TERM...Kremer/Myskowski SHORT TERM...Chai LONG TERM...Chai AVIATION...Myskowski ####018008533#### FXUS64 KBMX 040538 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 1238 AM CDT Sat May 4 2024 ...New AVIATION... .SHORT TERM... (This evening through Saturday) Issued at 145 PM CDT FRI MAY 3 2024 Key Messages: - Chances for showers and some thunderstorms will increase through the afternoon, becoming widespread late this evening through much of the overnight hours. - Storm motions are fairly slow with rain rates in excess of an inch per hour, areas that receive multiple rounds of heavy rain could experience ponding or water with limited potential for highly localized flooding. - Patchy fog may develop overnight due to the widespread heavy rainfall. This afternoon. A shortwave trough is positioned over the Lower Mississippi River Valley Region at midday while mid-level ridging was located over much of Florida and the Bahamas. A diffuse thermal gradient was observed in surface analysis across the northern third of the area where a weak boundary remains present. Through the morning and into midday, this feature has acted as a focus for persistent and additional development of shower and some thunderstorm activity. A cold front was analyzed from Northern Michigan that extended southwest across the Mid Mississippi River Valley and further southwest into Northern Texas. Expect rain chances through mid afternoon to continue to be maximized generally north of the Interstate 20 corridor with an additional area for increase across our western counties as activity continues to develop just head of a convective cluster of showers and thunderstorms that continues to move east across much of Mississippi. This activity is moving about 20 mph, which is slow enough to drop heavy rainfall as rain rates are in excess of an inch per hour to our west currently. There will be limited potential for some ponding of water and perhaps localized flooding if an urban or low-lying area experiences persistent or multiple rounds of heavy rainfall over time this afternoon into tonight. From mid afternoon through early evening, widespread showers and isolated thunderstorms will develop and move into the area from the west with the greatest coverage across the northern and western portions of the area. Winds will be from the southwest at 6-12 mph. Highs will range from around 80 far northwest to near 90 far southeast. Tonight. The mid-level shortwave will move over the are overnight, continuing to support showers with some thunderstorms across the northeast and central portions of the area. This activity will become more confined through the early pre-dawn hours on Saturday across our northeast and far eastern counties. With shower activity tapering off in the pre-dawn hours, low- level moisture will be high and some patchy fog is anticipated, especially for areas that receive heavier rainfall this afternoon through late tonight. Winds will be generally from the south to southwest overnight with speeds from 3-6 mph. Low temperatures will be in the lower to mid 60s areawide. Saturday. The mid-level shortwave will move east over Georgia by early afternoon while a weaker shortwave moves over the Mid-South Region toward mid afternoon on Saturday. A surface cold front will move east, extending from near Chicago and extending southwest across the Ozarks and into the Southern Plains by Saturday evening. A few remnant outflow boundaries from previous convection may remain across the area during the day, providing low-level convergence forcing to permit continued chances for showers and some thunderstorms. The better chance appears to be across the northeast half of the area, but at least isolated showers and storms are expected to develop across the rest of the area through the afternoon hours as the pattern remains unsettled with sufficient heat and humidity to support shower and thunderstorm development. Winds will be from the southwest at 5-10 mph. High temperatures will range from the low 80s northeast to near 90 southwest and far southeast. 05 && .LONG TERM... (Saturday night through next Thursday) Issued at 345 PM CDT FRI MAY 3 2024 Long term forecast is on track today, with no significant changes needed. There will be several opportunities for rain, especially across the north through the week. Expect warm temperatures as well, with lower 90s for at least the southern half of the area by Wednesday. 14 Previous long-term discussion: (Saturday night through next Thursday) Issued at 253 AM CDT FRI MAY 3 2024 Weak quasi-zonal flow aloft continues Sunday, with yet another convectively enhanced shortwave/MCV moving in from the Plains during the late afternoon and evening hours. PWATs around 1.8 inches will be favorable for scattered to numerous showers and storms developing with daytime heating, highest chances north. The shortwave appears a touch slower than previously forecast and have raised PoPs Sunday evening. Shortwave ridging in advance of the shortwave trough should allow temperatures to warm into the mid to upper 80s ahead of convection. A deep trough will eject across the Central and Northern Plains Monday with ridging building ahead of it. The prior weak shortwave may still be close enough to some of the northeastern counties to enhance diurnal convection there. The deep trough remains across the north-central CONUS on Tuesday as ridging builds over the Southeast CONUS. Strengthening low-level southwesterly flow will cause efficient mixing and warming temperatures/lowering dew points especially across the southeast half of the area, suppressing convection. But moisture pooling ahead of a stalled frontal boundary may remain sufficient for isolated to scattered convection in the northwest counties. Wednesday and Thursday a trough with a strong positive tilt will extend from the Great Lakes to the Four Corners while subtropical ridging strengthens over the Gulf. The tightening mid-level height gradient between these two features will result in strengthening WSW flow aloft. A quasi-stationary frontal boundary will reside across the Mid-South with several waves of low pressure riding along it. A strong EML will result in a very unstable air mass south of the front with strong deep layer shear as well. An early spring heatwave with near record highs looks likely across the southern counties. Will have to watch any convective disturbances skirting near the northern counties along the northern fringes of the warmer 700mb temperatures given a conditionally favorable environment for severe storms. 32/Davis && .AVIATION... (06Z TAFS) Issued at 1228 AM CDT SAT MAY 4 2024 A moist low level air mass will persist over Alabama thru 15Z. An upper level low currently over Alabama will produce sct to nmrs mostly light showers along and east of I-65 thru 18Z, with sct shwrs and isolated TSRA east of I-65 after 18Z. Vsbys not likely to fall below 3 miles with any shower or tstm. Mostly mid level clouds thru 09Z, with widespread MVFR cigs and lcl IFR cigs north of I-85 from 10Z thru 15Z. VFR cigs expected after 15Z. 58/rose && .FIRE WEATHER... Periods of showers and storms are forecast through Sunday. Given the scattered nature of the activity, rain amounts will average near one-half inch, with higher amounts where thunderstorms track. With increasing moisture, minimum RH values will be above 40 percent each afternoon. 20-foot winds should average less than 10 mph from the south to southwest, though could gust to around 25 mph and be variable in direction in or near thunderstorms. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 81 61 85 62 / 50 30 60 50 Anniston 82 63 85 65 / 50 30 60 40 Birmingham 82 65 85 66 / 20 20 60 50 Tuscaloosa 86 65 87 66 / 20 20 50 40 Calera 85 65 85 66 / 20 20 50 40 Auburn 85 65 85 67 / 30 20 50 30 Montgomery 87 65 88 67 / 20 20 40 20 Troy 88 64 88 65 / 20 20 30 10 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...05 LONG TERM....14 AVIATION...58/rose ####018010540#### FXUS61 KBOX 040538 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 138 AM EDT Sat May 4 2024 .SYNOPSIS... High pressure brings dry weather with cooler onshore breezes through Saturday. A slow-moving frontal boundary brings clouds and rain showers on Sunday into early Monday, along with a period of cooler high temperatures. Though clouds and off and on showers may linger in southeast New England in vicinity of the slowing front, drier weather prevails for most of interior Southern New England. Turning warmer on Tuesday with abundant sunshine, and though temperatures will be significantly cooler near the coast, interior areas could see high temperatures reach near 80 degrees. Our next chance for rain is around midweek. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 740 PM Update: Tranquil early-evening underway across Southern New England, governed by a 1024 mb high pressure area located in the waters east of Ipswich Bay. This high pressure remains generally stationary over at least the next 24 hours, maintaining dry weather but with an increase in cirrus/high clouds as the evening progresses. Used some of the RAP to show a decrease in sky cover for most of the evening, thus pleasant conditions for any Friday evening outdoor plans. However the fly in the ointment arrives by the pre-dawn hrs and mainly in eastern MA, in the form of marine-layer stratus which is evident in satellite imagery over Nova Scotia and the Bay of Fundy. These low clouds should gradually build/spread southwestward through the Gulf of Maine into Cape Cod and the adjacent eastern coastal waters toward daybreak. Think greatest extent of low cloud cover should be restricted to the immediate eastern MA coast, with scattered lower clouds further inland to around central MA/RI by daybreak. Low temps in the low-mid 40s seem on track for now with expectation of generally clear skies for most of the evening, with cooling likely not to be impeded by advancing stream of high clouds. Previous discussion: Good amount of wind shear visible on the satellite this afternoon with mid level clouds moving NE to SW and upper level cirrus moving NW to SE this afternoon. As for those mid clouds, the May sun is helping to increase our breaks of sun but partly cloudy is about the best we can hope for in much of southern New England for the rest of the day. By the overnight hours we'll see some marginal clearing of both mid and high clouds, especially after midnight, but fully clear skies aren't expected. Even so, given the high overhead and calm winds, did lower temps a but to account for some potential to radiate. Lows bottom in the low to mid 40s; right around average for early May. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/... High pressure nudges further south into New England from Nova Scotia bringing continued quiet weather for the first half of the weekend. This means continued cool, moist onshore flow from the northeast so low clouds will be moving in from the northeast while high clouds move in from the southwest. High temperatures won't be too different than Friday, with the warmest spot (the CT valley) in the upper 60s and the coolest spot (eastern MA) in the mid 50s. Cloudcover continues to increase overnight as deeper moisture (PWATs over 1 inch) move into western SNE on SW flow ahead of the approaching system. However, rain should hold off until after 8am. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Highlights: * Cloudy, cooler with rain on Sunday into early Mon, with continued lighter showers on Mon for southeast New England. * Dry and turning mild on Tue, though cooler onshore flow near the coasts. Spot 80s in the CT Valley? * Next chance for rains around midweek (Wed/Thu), though still unclear which day has the higher rain chances. Details: Sunday and Monday: The 12z suite of guidance continues to come into better congruence regarding our next chance for steadier light rains associated with a passing frontal boundary and a rather disorganized 500 mb trough. Chances for rain increase during the morning in most areas, with the period of greatest rain chances focused during the Sunday afternoon to early Monday morning period as the frontal boundary slowly shifts eastward. With the front becoming parallel to the 500 mb flow with time as we move into the early Monday period, expect lingering rain showers during the morning hrs along the RI/MA South Coast, Cape Cod and the Islands. Further north and west, we should see dry weather but with a mix of clouds and sun. Overall not a soaking rain, but enough to likely put a damper on outdoor plans for many on Sunday, with rain showers lingering into Monday for the southeast New England coastal areas. To that end, model-ensemble probabilistic QPF assessment shows high (70-90%) probs of 24 hr rain totals over a tenth of an inch, but lower to moderate (25-50%) probs for rain amts at or over a half inch. Official forecast has rain amts around a quarter to third of an inch. Expect Sunday to be a cooler day with cloud cover and rains around, with narrower diurnal range in high and low temps. Highs Sunday in the mid 50s, and lows in the upper 40s to near 50. High temps are more challenging on Monday with more clouds south of the Mass Pike and especially near southern coast, with some sunny breaks further north. Highs along the southern coast probably struggle to reach 60, but you don't have to go much further inland before highs reach into the low to mid 70s; with lows in the mid 40s to low 50s. Tuesday: High pressure over interior northern New England governs weather conditions into Southern New England Tuesday, supplying dry weather and mostly sunny conditions. An early look at model forecast soundings in interior MA/CT show potential for temperatures to overachieve guidance with progged deep mixing; with 850 mb temps around +7 to nearly +10C, highs could reach around 80 degrees in the CT Valley with readings well into the 70s eastward into RI and into the MA coastal plain. Northeast flow near the coast will keep temps several degrees cooler than well inland though, in the mid to upper 60s. Very difficult to show that level of granular detail given model-resolution limitations at this forecast time horizon and utilized some of the bias-corrected temperature fields given a similar regime. Did note NBM was advertising some low PoPs in this period for spot showers, but feel this is pretty overdone given progged mixing. Wednesday and Thursday: Though this period offers the next best chance for rain associated with an elongated warm front from low pressure over the Plains states, there is more uncertainty in timing when chances are greatest. Really will need those uncertainties to become more in clearer focus before delving into specifics. Didn't make too many adjustments to NBM in this period, except capped PoPs at the higher end of Chance range (40-50%) given stated timing uncertainties. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 06Z TAF Update: Through 12Z: High confidence. VFR conditions persist through 12Z with light and variable winds becoming more steady out of the east/northeast by sunrise. Today...Moderate confidence MVFR level cloud bases move onshore this morning from the east, but there is a bit of uncertainty with respect to sky cover. Humidity in the low levels is choppy, so coverage may range from SCT to BKN at times. So expect intermittent periods of MVFR ceilings for the first half of the day until the skies fill into BKN/OVC buy mid-afternoon/evening. Steady east/northeast winds from 5 to 10 knots. Tonight...High Confidence MVFR/IFR ceilings return overnight with continued light easterly winds. Winds becoming more east/southeasterly by 12Z Sunday. Tomorrow...High Confidence MVFR borderline IFR ceilings for most of the day tomorrow with -RA spreading from west to east during the day. Southeast winds becoming more southerly by hte afternoon. KBOS TAF...Moderate Confidence High confidence in MVFR cloud bases, but less confidence in coverage. There may be intermittent periods of SCT/BKN VFR/MVFR ceilings. KBDL TAF...High confidence in TAF. Outlook /Sunday Night through Wednesday/... Saturday Night: Mainly VFR, with local IFR possible. Sunday: Mainly VFR, with local IFR possible. Chance SHRA. Sunday Night: MVFR/IFR conditions possible. SHRA. Monday: Mainly VFR, with local IFR possible. Slight chance SHRA. Monday Night through Tuesday: VFR. Tuesday Night: VFR. Chance SHRA. Wednesday: Mainly VFR, with local MVFR possible. Chance SHRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Marine This evening through Saturday night... High pressure supports fairly calm conditions across the coastal waters through Saturday night. Winds will prevail out of the northeast from 10 to 15 knots with some gusts to 20 knots possible. Seas generally 1 to 3 feet. Outlook /Sunday Night through Wednesday/... Saturday Night: Winds less than 25 kt. Sunday: Winds less than 25 kt. Chance of rain showers. Sunday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Rain showers likely. Monday: Winds less than 25 kt. Seas locally approaching 5 ft. Chance of rain showers. Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. Tuesday: Winds less than 25 kt. Slight chance of rain showers. Tuesday Night through Wednesday: Winds less than 25 kt. Chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...None. && $$ SYNOPSIS...Loconto/BW NEAR TERM...Loconto/BW SHORT TERM...BW LONG TERM...Loconto AVIATION...RM MARINE...Loconto/BW