####018006757#### FXUS63 KJKL 031100 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 700 AM EDT Fri May 3 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 700 AM EDT FRI MAY 3 2024 Made a quick early update to the forecast grids. Based on obs from the past few hours, temperatures have simply not fallen off as far as originally forecast, especially in our normally cooler eastern valleys. Therefore, modified this mornings lows to reflect the latest obs trends. Will leave the zone forecast text product as is to continue covering early morning shower activity. Another update will be needed in the next hour or two to remove the pre- first period and make any further necessary updates. && .SHORT TERM...(Today through Saturday) Issued at 500 AM EDT FRI MAY 3 2024 The 6Z surface chart out of the WPC showed a large occluded low in place over northwestern Minnesota, with an occluded front extending southeast from it. A cold front and semi-stationary boundaries were snaking their way southwest and east from the triple point with the occluded boundary, with each boundary extending out to the east coast and beyond and out to western Nevada. Waves of low pressure were also seen at various locations from Utah to southwest Texas, to Indiana, and just off the Mid-Atlantic coast. High pressure was in place over portions of the central Plains and upper Mississippi Valley, with large subtropical low in place off the southeastern CONUS. A complex pattern in place across the country to be sure to start off this Friday. We will see showers and thunderstorms moving through our area from time to time today through Saturday, as the occluded low moves eastward into the Great Lakes and eventually into central New England. As the low moves off to the east or northeast, the surface boundaries extending south from it will move through the region, and will spark showers and storms across area. Based on current model data, it is clear that there will be instability and moisture in place to fuel showers and thunderstorms across eastern Kentucky, but uncertainty exists as to exactly where storms will fire and how extensive the rain will be. Some models have been showing few if any showers and storms across eastern Kentucky over the next couple of days, while others have fairly extensive coverage of precipitation. There is also some doubt revolving around how well defined any boundaries will be as they move through our area. That all being said, with a good influx of moisture and instability into the region, we expect scattered to numerous showers and scattered storms to fire and move through the area from time to time today through Saturday, with the afternoon and early evening hours being most active due to peak heating and maximized instability. It does appear that Saturday will be a bit more active than today, as the model data is showing quite a bit more instability present than today, especially late Saturday afternoon. Temperatures will continue to run well above normal, with highs in the upper 70s to lower 80s on tap today and Saturday. Enough decoupling may occur late Friday night to allow for a small ridge valley split, especially in the northeast where our normally cooler valleys may fall off into the mid 50s. As far as weather hazards go, we are not expecting anything of major concern at this time. As always, any thunderstorms we see the next couple of days will be capable of producing dangerous cloud to ground lightning, gusty winds, and locally heavy downpours that could lead to ponding of water on roadways or short lived minor nuisance flooding. Confidences is high that most locations will see rain today through Saturday, its a matter of how widespread will thunderstorms be, especially today with less instability expected. .LONG TERM...(Saturday night through Thursday) Issued at 500 AM EDT FRI MAY 3 2024 A rather wet long term period should be in store. However, it looks overall rather short on details/specifics. Prevailing large scale flow aloft will be persistent from the west southwest, while low level flow will be from the south southwest off the gulf. This pattern of warm/moist advection will favor precip. A wavering frontal boundary will approach from the northwest at times, but being largely parallel to the upper level flow, it will not have much momentum and is not likely to make a clean passage during the period (possibly just beyond the current long term period). This will leave us in a modestly humid air mass with surface dew points in the upper 50s and lower 60s most of the time. The main drivers for precip will be convection associated with diurnal heating cycles and mid/upper level waves. While the diurnal cycle is simple, weak upper level features are much more problematic. The most obvious and predictable feature at this point is a shortwave trough which all models have approaching on Monday. The highest POP (70% area wide) of the long term period coincides with this. The remainder of the 12 hour periods have POPs mainly in the 40-60% range. && .AVIATION...(For the 12Z TAFS through 12Z Saturday morning) ISSUED AT 700 AM EDT FRI MAY 3 2024 Scattered rain showers have begun moving into our southwestern counties early this morning, with SME and LOZ seeing the first rain. VCSH is being used to handle the early morning activity, but it appears that enough thunderstorms will fire by early this afternoon to warrant inserting VCTS into each TAF, beginning at 18Z for SME and starting at 23Z or so at JKL and SJS. The best time for any storms will be this afternoon into early this evening during peak heating. Once the sun goes down, the storms should become more isolated with time with rain showers being the dominant precipitation mode. Rain will become more widespread as the day wears on, with numerous light to moderate rain showers expected this afternoon through late this evening. Any storm could produce locally heavy rainfall and gusty winds, along with brief periods of MVFR VSBYs. MVFR CIGs will also be possible at times today into this evening during peak thunderstorm activity. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AR SHORT TERM...AR LONG TERM...HAL AVIATION...AR ####018005774#### FXUS63 KILX 031100 AFDILX Area Forecast Discussion...Updated Aviation National Weather Service Lincoln IL 600 AM CDT Fri May 3 2024 .KEY MESSAGES... - Scattered showers and isolated thunderstorms diminish from the west during this morning, with isolated showers lingering near the Wabash river this afternoon. Cooler highs in the mid 70s today. - Level 1 (marginal) risk of severe thunderstorms from mid Saturday afternoon into mid Sat evening over all but far eastern IL for gusty winds and hail. - An active weather pattern re-establishes itself Monday through Thursday, with signals showing risk of strong to severe storms Tuesday and Wednesday especially during afternoon and evening hours. && .DISCUSSION... Issued at 400 AM CDT Fri May 3 2024 Predawn surface map shows a cold front near I-55 with scattered showers along and east of the front and more numerous near the Indiana border. IR Satellite loop shows clouds over much of CWA while clearing skies just nw of Galesburg, Macomb and Quincy. Temperatures ranged from mid to upper 50s west of the IL river, to the mid 60s from I-70 southeast. Cold front to push east of IL/IN border by mid morning with scattered showers and isolated thunderstorms diminishing as cold front passes by. Though isolated showers still possible over the Wabash river valley this afternoon. Clouds to decrease over nw half of CWA during today, with mostly sunny skies by mid to late afternoon from I-55. Meanwhile skies stay cloudier over southeast part of CWA today. Winds turning NE behind the front at 5-15 mph so much lighter than past few days. Cooler highs today in the mid 70s, except upper 70s possible from highway 50 south in southeast IL. Weak high pressure ~1018 mb over western IA drifts over WI and lower MI by sunset and ridging into central IL much of tonight and bringing fair weather. Some fog development noted east over parts of upper Wabash river valley of Indiana and gets close to Vermilion county/Danville area by sunrise Sat. Will keep fog out of forecast overnight and early Sat morning but will need to watch areas near the Indiana border. Lows overnight range from the lower 50s west of I-55 (upper 40s by Galesburg), to the lower 60s in southeast IL. A short wave trof over the northern Rockies by Idaho and western MT to track eastward into the eastern plains by midday Saturday and push a cold front east through central IL late Sat afternoon and evening. Air mass gets unstable Sat afternoon with CAPES rising to 1000-1800 j/kg by mid to late Saturday afternoon while wind shear values are 15-25 kts. Isolated to scattered thunderstorms to develop during mid/late Sat afternoon and continue into Sat evening. SPC introduced a marginal risk of severe storms over all but far eastern/se IL from Watseka to Charleston to Mt Vernon west for gusty winds and hail from mid Sat afternoon through mid Sat evening. Highs Saturday around 80F to lower 80s with dewpoints back up in the low to mid 60s. Convection chances diminish overnight Saturday night and Sunday morning and mainly 20-30% chance in southeast IL by Sunday morning. A short wave moving ne into the Ozarks late Sunday to increase chances of showers and isolated thunderstorms in mainly southeast IL during Sunday afternoon with isolated showers possible late Sunday afternoon about as far north as I-72. Instability is weaker on Sunday so not in a threat of severe storms on Sun afternoon and evening. Highs Sunday in the lower 70s over central IL and 74-78 in southeast IL. The weak short wave trof lifts into southern/sw IL by dawn Monday and into the central Ohio river valley late Monday afternoon, and likely brings showers and chance of thunderstorms into southeast IL Monday while lower chances over northern CWA. SPC day4 outlook for Mon/Mon night keeps severe risk area well west of IL over the central plains centered over central KS. Highs Mon in the mid to upper 70s. Forecast models continue to show a large/strong mid/upper level trof evolving over the Rockies early next week, and ejecting strong low pressure from CO into ND Tue night and into the upper MS river valley Wed night. There will be periods of showers and thunderstorms over IL from this large storm system Tue through Thu with strong to severe storms possible Tue afternoon into Wed evening. SPC Day5 outlook has 15% risk of severe storms over IL Tue afternoon/evening. SPC Day5 outlook has 15% risk of severe storms se of IL on Wed/Wed night, but would not be surprise to see this expanded ne into parts of central and southeast IL Wed afternoon/evening as instability is decent on Tue and Wed with strong wind shear in place. Warm highs Tue/Wed in the lower 80s, except upper 70s nw of the IL river on Wed. Best chances of convection along with possible strong to severe storms shift se of CWA on Thu though still have low pops on Thu especially se half of CWA. Cooler and less humid air arrives on Friday and next Saturday with seasonable highs in the upper 60s/lower 70s. 07 && .AVIATION... (For the 12z TAFs through 12z Saturday Morning) Issued at 600 AM CDT Fri May 3 2024 A cold front was pushing through central IL early this morning, causing initially light/calm winds to go northwest/north later this morning and then northeast this afternoon near/under 10 kt. A narrow band of MVFR ceilings follows to front. These should scatter out by midday, with VFR high clouds to follow through 12z. 25 && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ ####018005955#### FXUS64 KMRX 031101 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 701 AM EDT Fri May 3 2024 ...New AVIATION... .SHORT TERM... (Today and tonight) Issued at 330 AM EDT Fri May 3 2024 Key Messages: 1. Increasing chances of showers and storms this morning through the evening, with a potential lull in activity overnight. 2. While severe weather is not expected, a few instances of small hail, wind gusts up to 40 mph, and locally heavy downpours are possible this afternoon. Discussion: Upper level disturbances will bring increasing chances of showers and storms to the forecast area today. Regional mosaic radar already depicts a rain shield moving into western Kentucky, central Tennessee, and eastern Mississippi this morning. Precipitation chances will gradually increase across our forecast area through the morning hours, with just general rain showers as the predominant weather type. As we transition into the afternoon hours, hi-resolution models suggest development of MLCAPE in the 300-800 J/kg range, which will lead to increasing chances of thunder. A weak shear profile and mid level lapse rates struggling to reach 6C/km should keep any storms from reaching severe levels, although, any stronger storm could lead to locally gusty winds up to 40mph and pea-size hail. PWAT values will generally approach near 1.4 inches. This is around the 90th percentile based on sounding climatology out of BNA. As such, we cannot totally rule out some isolated flooding concerns with any slow moving or training convection this afternoon. Thankfully, below normal rainfall over the last month has allowed for 1 hr FFGs of 1.8-2.3" across the forecast area, really minimizing this threat. A marginal risk for excessive rainfall covers areas generally along and west of I-75 - where the better chance for relatively more effective convection exists. Temperatures will typically be near normal. Ensemble guidance suggest we may see a window of little to no activity during the late evening/overnight hours. && .LONG TERM... (Saturday through Thursday) Issued at 330 AM EDT Fri May 3 2024 Key Messages: 1. An unsettled pattern is expected through the extended period with daily scattered to numerous showers and storms. More organized convection is possible by Wednesday/Thursday of next week. 2. Temperatures will be generally above normal, especially next week. Saturday through Monday At the start of the period, a fairly weak upper-level flow pattern will be in place with a shortwave moving in from the west. With broad moisture and surface heating, Saturday will consist of scattered to numerous convection throughout the day. Based on the weak flow, the convection will be thermodynamically-driven as very minimal shear will be present. Overall, instability will be fairly typical of the summer, i.e. near 1,000 J/kg of MLCAPE. PWATs will also be 1.4 inches or higher, which is around the 90th percentile for this time of year. With these conditions, some stronger storms with gusty downburst winds are possible, in addition to locally heavy rainfall rates. Thankfully, fairly dry conditions, including low-end drought, will keep any flooding concerns very localized. Heading towards Sunday, gradual height rises are expected with embedded shortwave energy and similar thermodynamic conditions. This will lead to slightly warmer temperatures than on Saturday with additional showers and storms expected. A closed upper low will also be noted to our west and will approach towards Monday. This may lead to slightly better coverage than on Sunday, but the overall impact will be the same. Tuesday through Thursday The unsettled pattern will continue into the middle of the week with continued embedded shortwave, broad moisture, and surface heating on Tuesday. By Wednesday to Thursday, however, a more dynamic pattern is anticipated with the upper jet (in excess of 100 kts) dipping further south. Upper-level divergence will help to strengthen the 850mb, possibly to in excess of 40 kts. A surface front will also slowly drift southward. While discrepancies still exist, these indications suggest an environment with potentially better thermodynamics and deep-layer shear sufficient for more organized convection than in the earlier part of the extended period. At this time, low probability HWO wording will be kept to encompass the multiple rounds of convection and potential locally heavy rainfall. However, the Wednesday to Thursday timeframe will be something to watch for more organized and/or robust convection. && .AVIATION... (12Z TAFS) Issued at 659 AM EDT Fri May 3 2024 VFR conditions will be predominant through the TAF cycle, with mid to low level BKN/OVC clouds increasing through the morning into the afternoon. Continue to expect increasing chances for a few thunderstorms by the afternoon. Rain chances increase late morning to mid-day at TRI but have kept thunder omitted. Recent hi- resolution guidance suggest by late Friday evening activity becomes more isolated so have transitioned the mention of showers and storms to vicinity. Development of MVFR cigs is possible early Saturday morning. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 81 65 79 64 / 50 50 70 40 Knoxville McGhee Tyson Airport, TN 77 63 78 63 / 70 50 80 50 Oak Ridge, TN 77 63 78 62 / 80 50 80 50 Tri Cities Airport, TN 77 61 76 60 / 60 50 80 60 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...KRS LONG TERM....BW AVIATION...KRS ####018005147#### FXUS61 KCTP 031102 AFDCTP Area Forecast Discussion National Weather Service State College PA 702 AM EDT Fri May 3 2024 .SYNOPSIS... -Not as warm but pleasant end to the week with increasing clouds -Noticeable cool down over the weekend with periods of rain -Remaining unsettled next week with a gradual warming trend && .NEAR TERM /THROUGH TONIGHT/... Sunshine to start today will be followed by increasing clouds into tonight. High pressure channeling down the eastern slopes of the Appalachians will maintain dry wx over the majority of the CWA (eastern 2/3) through 00Z Sat with max POPs to the west of the US219 corridor. This area should be in the warm sector where the most unstable air will reside. A couple of locally heavy t-storm downpours with spot amounts >1" will be possible on the edge of higher pwat air surging in from the upper OH Valley. The 24hr maxTchange will be considerably cooler over the central and southeastern ridge/valley region this afternoon with fcst highs giving back 7-15 degrees from yesterdays near- record to record breaking temps. Shower activity should eventually expand west to east through tonight as an increasingly moist east/southeast flow brings widespread low clouds and perhaps some fog/mist on the ridgetops. Still downplaying non-severe t-storm potential given increasing low level stability/CAD pattern setup and lack of MUCAPE. Low temps will be above early May climo and range between 45-55F from the southwestern Poconos/Coal Region to Warren County. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... Hires models show CAD pattern firmly entrenched over CPA on Saturday, and therefore we continued to trim max temps vs. NBM. No risk of thunder on Saturday so removed from wx grids and changed character of precip to rain from showers. Rain/showers continue through Sunday night with highs recovering 5-10F over the southwest 1/2 of the CWA. Some isolated convection is possible in this area Sunday PM as the warm sector shifts to the east. Despite the relatively high moisture availability, limited rain rates should keep blended mean QPF btwn 0.50-1.00 inches ending 00Z Monday. Fcst lows Sunday night will be +10-15F above climo for early May in the 50-60F range. && .LONG TERM /MONDAY THROUGH THURSDAY/... The extended period will trend milder and remain unsettled with several chances for rain. A cold front will stall near or south of the MD line Monday and Tuesday before lifting to the northeast (as a warm front) into midweek. The favors the best chance for rain the SW zones on Monday before POPs increase to 50-70% Tuesday into Wednesday. After a weekend cooldown, temps will trend warmer/back above climo into the 70s to low 80s. With several chances for rain next week along with persistent mild temperatures, green up should rapidly expand into northern PA thus ending the spring fire weather season. Additionally, there is no chance for frost or freeze conditions through the end of the week. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... VFR/unrestricted conditions should remain in place across central PA terminal sites into this evening. Confidence on this scenario is fairly high (70-90%). An area of showers could reach the Allegheny Highlands late in the day (as early as 21-22z) and perhaps bring fuel alternate- MVFR restrictions at KJST and KBFD. The threat for MVFR cigs then increases substantially between 22z Fri and 02z Sat across the Laurels and Alleghenies, including JST, BFD, AOO, and UNV. Conds will continue to deteriorate Fri night into early Sat morning as southeast onshore flow advects cooler, moist air from the North Atlantic. IFR cigs are likely (60 percent chance or higher) for most TAF sites by 12z Sat, with the exception of IPT. Light surface winds will increase out of the SE to 5-10 kt Friday. Occasional gusts of around 20 kt could occur in the afternoon. Southeast flow will continue into Saturday. Outlook... Sat-Sun...Widespread restrictions due to low cigs. SHRA likely with a chance of TSRA. Mon-Tues...AM fog/clouds poss. PM -SHRA possible areawide. && .CLIMATE... Several records were tied or set on Thursday May 2nd: SITE OBSERVED TEMP PREVIOUS RECORD Altoona 87F 87 in 1954 Harrisburg 90F 88 in 1913 State College ??* 86 in 1938 Williamsport 89F 89 in 2018 *Official report from State College will be available Friday morning. May 2nd was also the first 90F day at Harrisburg. It is the 13th earliest 90F day on record. The earliest 90F day occurred on April 17th in 1896 and 2002. The average first 90F day is June 1st. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Steinbugl LONG TERM...Steinbugl/Banghoff AVIATION...Jurewicz/Colbert CLIMATE...Steinbugl/Banghoff ####018007404#### FXUS64 KHGX 031104 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 604 AM CDT Fri May 3 2024 ...New AVIATION... .SHORT TERM... (Today through Saturday Night) Issued at 302 AM CDT Fri May 3 2024 The current "lull" in shower/storm activity across SE Texas looks to be coming to an end, as isolated shower/storms have begun to develop across the region. High-resolution models indicate rain chances increasing throughout this morning as a shortwave passes overhead, tapping into rich PWs of 1.75-2.00" to bring more showers/thunderstorms across the region. While the mesoscale environment will make things messy, guidance seems to hint at two main "clusters" of storms developing with this next wave. The first cluster appears to develop over the southern half of our CWA, talking on an E/NE track. While closer to the primary moisture axis, models seem to suggest more modest rainfall rates in this cluster. Meanwhile, the second cluster looks to develop further north over the Brazos Valley/Piney Woods area, tacking Southeasterly. Forcing with this system appears to be a tad more robust, located in the vicinity of the left exit region of the upper level subtropical jet, which also appears to coincide with a convergence zone with the 925mb LLJ during the afternoon. Some short term guidance suggests that rainfall rates would be higher in this cluster. Crest shows swaths of soil moisture in excess of 40% in areas north of I-10, peaking in excess of 70% over portions of Walker & Trinity counties. RFC 1hr FFG for much of this same area is around 1.5-2.5", though lower values of under 0.5" encompass portions of Liberty/Harris counties. Overall the heavy rainfall threat will still encompass most of SE Texas, with a Flood Watch remaining in effect for most areas North of I-10 until 7 PM Tonight. The threat of heavy rainfall remains greatest early this morning, where WPC still has SE Texas under a Moderate (level 3/4) to Slight (level 2/4) risk of Excessive Rainfall. The threat of excessive rainfall subsequently decreases during the late morning/early afternoon to a Slight (level 2/4) to Marginal (level 1/4) Risk. Flood Warnings and River Flood warnings are ongoing across the region, and any additional heavy rainfall may further exasperate hydrological problems. Be careful while driving and avoid any flooded roadways. There looks to be a short reprieve from rainfall later today, with showers/storms tapering off this evening/tonight. Guidance still suggests the possibility of showers/storms developing again early Saturday morning, though the risk of excessive rainfall remains Marginal (level 1/4) during this period, mainly in our North/Northwestern Zones. Ample moisture and lifting from disturbances aloft will enable rain chances and flooding concerns to persist into the long term forecast. 03 && .LONG TERM... (Sunday through Thursday) Issued at 302 AM CDT Fri May 3 2024 One more day of scattered showers and thunderstorms is expected on Sunday as a stronger shortwave trough moves north of the area. At the surface, a weak boundary (warm front) will lift northward into SE TX during the day. Increasing theta-e advection, sufficient moisture and instability will lead to increasing precipitation chances during the day. Unfortunately, the bulk of this activity looks to occur again north of I-10; however, rainfall totals are progged to remain around a half inch or less. The main weather story in the medium range evolves in the increased heat risk. A relatively dry weather is expected through most of the week. However, a quasi-zonal flow aloft, and south to southwest flow at the surface will lead to above normal temperatures. 850mb temperatures will warm into the upper teens to mid 20s degC range during the week, suggesting highs in the 90s. Based on latest models solutions, Thursday is shaping up to be one of the hottest days with highs generally into the mid 90s. These values are within the 99th percentile of climatology per NAEFS and GEFS. These readings are progged to be 5 to 10+ degrees above normal for this time of year. JM && .AVIATION... (12Z TAF Issuance) Issued at 552 AM CDT Fri May 3 2024 MVFR to IFR CIGS will slowly begin to lift this morning, climbing back to VFR levels this afternoon. Scattered showers & thunderstorms will taper off this evening, with more MVFR/IFR CIGS developing overnight into Saturday. Southeasterly winds prevail throughout the TAF period. 03 && .MARINE... Issued at 302 AM CDT Fri May 3 2024 Moderate southeast winds, seas between 3 to 6 ft and isolated to scattered showers and thunderstorms are expected today and tonight. Gusts from 15 to 20 knots will be possible at times, stronger around any thunderstorms. Therefore, Small Craft Should Exercise Caution Conditions will continua today for all bays and Gulf waters. Moderate to occasionally strong onshore winds and seas from 3 to 6 ft should remain through the weekend and into the upcoming week. Seas can reach advisory levels (around 7 ft) at times well offshore. Rain and storm chances decrease during the weekend, bringing benign marine conditions into next week. JM && .HYDROLOGY... Issued at 302 AM CDT Fri May 3 2024 There is ongoing river flooding over parts of Southeast Texas, particularly along portions of the Trinity and San Jacinto rivers. The following river points are at, or forecast to go to Major flood stage: - Trinity River (Madisonville): Major Flood Stage - Trinity River (Liberty): Major Flood Stage - Trinity River (Goodrich): Major Flood Stage - West Fork San Jacinto (Conroe): Major Flood Stage - West Fork San Jacinto (Humble): Major Flood Stage - East Fork San Jacinto (Cleveland): Major Flood Stage - Caney Creek (Splendora): Major Flood Stage - Trinity River (Romayor): Minor forecast to go to Major - Navasota River (Normangee): Minor forecast to go to Major - Menard Creek (Rye): Moderate forecast to Major - Trinity River (Moss Bluff): Moderate forecast to go to Major - East Fork San Jacinto (New Caney): Moderate forecast to go to Major - Peach Creek (Splendora): Moderate forecast to go to Major - San Jacinto (Sheldon): Moderate forecast to go to Major Remember to heed any instructions from your local officials and to never travel through flooded areas or roadways. Please monitor updated forecasts via the NWS AHPS website and/or the new NWS NWPS webpage (https://water.noaa.gov/) as the river flood threat continues.  JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 83 71 84 71 / 50 10 20 30 Houston (IAH) 83 72 84 73 / 50 10 10 20 Galveston (GLS) 80 74 80 74 / 50 10 0 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Flood Watch through this evening for TXZ163-164-176>179-195>200- 212-213-300-313. GM...Small Craft Should Exercise Caution through this evening for GMZ330-335-350-355-370-375. && $$ SHORT TERM...03 LONG TERM....JM AVIATION...03 MARINE...JM ####018008780#### FXUS61 KPBZ 031104 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 704 AM EDT Fri May 3 2024 .SYNOPSIS... Dry and unseasonably warm weather precedes increasing precipitation chances Friday afternoon and continuing through the weekend. Cooler, but still above average, temperatures prevail Saturday and Sunday with warm and unsettled weather continuing into next week. && .NEAR TERM /THROUGH TONIGHT/... KEY MESSAGES: - Showers and thunderstorms Friday afternoon and evening. - Temperatures well above average approaching a few records. ------------------------------------------------------------------- Did a morning update to refresh the forecast and incorporate current observations. Cirrus coverage is approaching. This upper deck appears quite optically thick on satellite, so opted to not nudge up temperature from NBM output. A thicker deck may suppress radiative heating slightly into the day today and suppress low cumulus fields, and potentially limit storm coverage slightly more. This will warrant watching into today. .. Previous Update .. High pressure will retreat off to the east as a disturbance approaches from the west. Cirrus coverage will thicken and lower through the morning with increasing upper level moisture. Forecast soundings suggest another day similar to Thursday with a quickly breaking nocturnal inversion and a dry boundary layer allowing for mixing up to nearly 700 mb. The 850 mb ridge will gradually shift to the east and allow for warm advection in southwesterly flow to bring layer temperatures up to 15-16C across the area by afternoon, suggesting that high temperature will achieve the mid to upper 80s despite the cirrus. A couple sites have the potential to approach record highs (see climate section). Some lingering uncertainty in ensemble cloud coverage with suggestions for periods of scattering as cirrus push to the east lends potential for additional insolation to push temperatures up even a degree or two higher than currently forecast. This also could aid in a bit more destabilization ahead of showers and thunderstorms expected to develop by afternoon. Indications are that showers and storms pop after 17z despite copious low level dry air (LCLs 6-8kft) as convective temperatures are met and a shortwave moves through, though weak net height rises through the day are expected. Mean hi res ensemble CAPE has increased in the latest run with 600-900 J/kg; conditional on potential scattering of clouds, the 75th percentile is up to 1400 J/kg. Most guidance suggests that warm mid-levels will suppress updrafts with an equilibrium level below about 500mb. Latest CAMs suggest that the best shot for deeper convection may be across eastern Ohio where slightly less warmth and moisture in the mid-levels may allow for greater vertical growth. Even if the higher end of the instability spectrum is achieved, weak cloud bearing layer flow will present a moderate CAPE/low shear environment likely more favorable of gusty wind with brief heavy downpours. PWATs will be pushing 1.5" and upwind propagation vectors around 10 knots despite practically no low level jet suggest this potential. HREF probs for >0.5"/hr rates reach up to around 60% by evening. As a result, the Weather Prediction Center has our area in a Marginal Risk (1/5) for excessive rainfall on Friday. Record low max temperatures may be broken Friday night with persistent cloud cover not allowing for radiative cooling. Convection is favored to wane as instability is lost and the upper wave departs. Nonetheless, scattered showers will continue overnight. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... KEY MESSAGES: - Unsettled pattern remains with rain chances continuing through Sunday. Thunder possible on Sunday. - Temperatures drop, but still remain above normal. ------------------------------------------------------------------- Come Saturday, there is some suggestion the trough progression will come to a halt and allow rain to persist ahead of it being reinforced by approaching low pressure and additional shortwave support arriving from the south. The positioning of the trough will have a great influence on the weekend weather. No significant changes to the forecast for Saturday as instability looks limited to the western side of the stalled boundary/trough with a 50-60% of >500 J/kg while elsewhere plenty of low to mid level warm air will cap the environment. Total rainfall Saturday is favored in the half to three quarters of an inch range. There is good agreement the trough finally pulls through by Sunday. An area of maximized precipitation ahead of or just along the trough axis is favored, as is a greater chance for more instability to work with. Ensemble probability for CAPE >500 J/kg reaches 70-80% Sunday, but with a good amount of clouds around and a low probability of any scattering. Still, with a bit better dynamics in play and marginal instability, a few thunderstorms accompanying the trough appear possible. Most likely total precipitation amounts Friday night - Sunday night sit around 1.0-1.3", but the 90th percentile exceeds 2" primarily across the WV panhandle and western PA resultant of some convective enhancement along the aforementioned trough. This does not raise any flooding concerns for now, but may warrant watching if the higher end becomes more likely. Thick cloud coverage through the weekend will hold temperatures in check, but still above average, in the 70s. && .LONG TERM /MONDAY THROUGH THURSDAY/... KEY MESSAGES: - Rain chances continue into early next week but more uncertainty lends lower confidence. - Temperatures favored to remain above normal. ------------------------------------------------------------------- After a brief lull in the precip late Sunday night into early Monday morning as flat upper ridging slides through and surface high pressure meanders on by, rain chances again increase. Seeing some better ensemble agreement for Monday with shortwave low pressure approaching from the southwest but weakening as the responsible upper wave flattens out. High pressure to the north should keep the highest precipitation chances south of I-70. Much more ensemble spread comes into play after Monday primarily with the progression of the upper pattern as ridging tries to develop but a deep upper low across the Dakotas throws shortwave energy to the east and tries to break the ridge down. A warm front likely lifts through sometime Tuesday into Wednesday increasing rain chances again, but with uncertainty in the strength and positioning of the ridge, timing and precipitation amounts remain low confidence at this time. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... VFR conditions through most of the day, with high clouds increasing this morning and mid clouds this afternoon. Scattered showers and thunderstorms are expected to develop late this afternoon and evening. Expect locally lower ceilings and visibilities, lightning, and possibly some gusty winds to accompany any stronger storms. The probability that a storm will hit any particular port is low at this time so will use prob30 to cover the convection threat. Activity should dissipate with the loss of sunlight. Lower clouds are possible late tonight. .Outlook... Restriction potential continue through Saturday, then again early next week as multiple disturbances cross the region. && .CLIMATE... Some record highs may be approached on Friday as well as record lows on Saturday. (* denotes current forecast temperature exceeds value) 5/3 Record High Year Pittsburgh 95 1887 Wheeling 90 1942 Morgantown 88* 1965, 2012 New Philadelphia 89 2012 Zanesville 91 1938 Dubois 84 2012 5/4 Record Low Year Pittsburgh 65 1938 Wheeling 63 1931, 1939, 1941 Morgantown 63 2021 New Philadelphia 60* 2012 Zanesville 65 1902 Dubois N/A N/A && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...MLB NEAR TERM...MLB/Milcarek SHORT TERM...MLB/Milcarek LONG TERM...MLB AVIATION...22/Milcarek CLIMATE...