####018005156#### FXUS63 KDTX 181049 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 649 AM EDT Thu Apr 18 2024 .KEY MESSAGES... - Dry today with showers moving in late this evening along a cold front. A few rumbles of thunder cannot be ruled out. - Showers exit Friday morning with drier and cooler weather heading into the weekend. && .AVIATION... MVFR to lower VFR ceilings will clear out this morning, leaving some degree of cirrus this afternoon into evening. Additional MVFR cigs will arrive overnight tonight as an area of showers accompany a cold front. Some potential for IFR as well. Winds will vary considerably this forecast backing from WSW this morning to S this afternoon to E tonight and then WNW late as the cold front cross the area. While a rumble of thunderstorm is not out of the question, low probability does not warrant a mention in forecast as instability is marginal at best. .DTW THRESHOLD PROBABILITIES... * High for ceiling aob 5000 ft through this morning, then high again after 04z-06z tonight. && .PREV DISCUSSION... Issued at 340 AM EDT Thu Apr 18 2024 DISCUSSION... Brief window of ridge amplification occurs across the Great Lakes today, in between the shearing upper low to our northeast and an expansive stacked low that is located to our west over central Canada. Increasing cyclonic influence of the inbound low leads to a quick return of warm advection to support highs today in the mid to upper 60s. Wrap around moisture on the western flank of the departing system has slowly blanketed the cwa with a low stratus deck that will linger this morning. There is increasing support for a window of at least partial clearing this afternoon for the southern half of the cwa, but upstream lee cyclogenesis and return flow quickly advect the next round of moisture aloft. A stray shower or two will be possible as early as this afternoon across the Tri Cities and Thumb as a 700mb wind maximum around 50 knots initiates strong theta-e advection immediately following the ridge axis. Standard lag in low level moisture advection affords low coverage of any shower activity, favoring broader coverage of virga and cloud cover until low level moisture transport ramps up late this evening. Forcing will be maximized invof a lengthy baroclinic zone/cold front that originates from the Canadian low and extends into the Texas panhandle, so expecting a broken line of showers and embedded thunderstorms to track through between roughly 03z-12z (11pm-8am local). The cyclogenesis mentioned above yields a surface low that will track northeast along the boundary, which effectively keeps the warm sector and instability axis well south of the state line. Elevated thunderstorms do remain possible however, with mean HREF MUCAPE of 100-250 J/kg (some CAMs up to 500 J/kg), but severe weather is not expected. Progressive nature of this system keeps widespread QPF totals between a quarter to localized half inch by Friday morning. This cold front will draw in a notably colder and drier airmass Friday morning, evident as H8 temperatures drop below zero which locks daytime highs Friday-Sunday in the 50s, just a few degrees below climatology. Will see a gradual eastward drift to the governing Canadian low through the weekend which will maintain elevated boundary layer winds to support breezy conditions both Friday and Saturday. Otherwise, benign conditions expected through the weekend as high pressure expands across the eastern half of CONUS. Ensemble mean 500mb height anomalies give a strong signal for the upper low to stall over Hudson Bay early next week, with deterministic runs consistently steering a glancing shortwave toward the Great Lakes Tuesday. MARINE... A brief period of ridging expands over the central Great Lakes keeping westerly winds and subsequent waves to a minimum throughout today. Another cold front sags through the region late tonight into the first half of Friday bringing another shot at widespread showers as well as a slight chance for a couple non-severe thunderstorms over the southern Great Lakes. Upper level troughing settles over the Great Lakes following the frontal passage and will hold overhead through Sunday. Main impact is cooler air spilling back south creating a more favorable overlake thermal environment to support moderate west turning northwesterly winds through this weekend. Peak winds look to occur daytime Saturday though holding sub-gales instead topping out around 30kts over northern Lake Huron- 20-25kt gusts favored over the rest of the region. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....DG DISCUSSION...MV MARINE.......KDK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit. ####018005709#### FXUS62 KCAE 181052 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 652 AM EDT Thu Apr 18 2024 .SYNOPSIS... A warm and sunny day expected today with warm temperatures and no chance of rain. Moisture will increase Friday and Saturday as a cold front moves into the area. With strong heating, diurnally driven showers and thunderstorms are expected to develop. The front will become stationary near or slightly south of the area Sunday. Deep moisture and lift across the area will result in numerous showers Sunday through early Monday. Temperatures Sunday and Monday are expected to be well below normal. && .NEAR TERM /THROUGH TONIGHT/... Weak shortwave energy is crossing the region early this morning and should clear the high clouds out allowing for a mostly sunny day. PWATs will be falling below an inch this morning as drier air moves in behind the departing shortwave with some subsidence. Surface low pressure will lift northeastward from the Central Plains this morning to the western Ohio Valley by this evening pushing a cold front into the Mississippi Valley remaining well west of our area. Temperatures this afternoon should be warmer than yesterday with plenty of sunshine expected in addition to some downsloping flow with high temperatures expected to be in the upper 80s to around 90 degrees. Temperatures may approach record values at AGS (91 set back in 1896). Deep mixing within a drier air mass should result in low humidities as dewpoints fall into the 40s. Tonight, chances of rain increase after midnight as hi-res guidance shows some showers and possible thunderstorms developing ahead of the front to our west. There is some agreement that any activity that moves into the western Midlands will be weakening as it moves in and will be moving into a drier air mass so will only carry slight chance pops in the western Midlands and upper CSRA tonight. Overnight lows should remain above normal and be similar to this morning with lows in the lower to mid 60s. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... Shortwave will be moving through the area Friday morning as moisture increases with HREF mean PWATs climbing to above 1.2 inches. Some showers are possible associated with the shortwave from west to east, tapering off mid to late morning with a lack of forcing into the early afternoon limiting the potential for precip until a surface trough shifts into the area by late afternoon into Friday evening, strengthening low level convergence. With temperatures above average once again as highs rise into the mid to upper 80s, expect moderate destabilization with 70% of HREF members showing sbCAPE exceeding 1000 J/kg. CAMs indicate convection developing along the surface trough, mainly across the northern portion of the forecast area. SPC maintains a marginal severe risk over the entire area. Deep layer shear increases late in the day and while it will likely not be overly impressive, it will support organized multi- cells. Isolated damaging wind gusts or marginally severe hail will be possible with the strongest storms. Storms should dissipate Friday night with a loss of daytime heating. Lows remain mild, in the low to mid 60s. A cold front will be pushed into the area Saturday from the north and slowly move south through the area which will lead to a tighter temperature gradient with southern portions of the forecast area once again in the upper 80s but along the north, closer to 80. While upper forcing appears to be somewhat limited with zonal flow aloft, surface convergence along the front will support scattered showers and thunderstorms once again, although a bit more uncertainty as to the degree of instability across the forecast area. Chances for showers and even an isolated storm continue overnight with a shortwave expected to move in. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... The front will be near the southern border of the forecast area early Sunday morning with strengthening isentropic lift over the forecast area and a more robust shortwave moving in late in the day leading to widespread rain. Guidance continues to trend more towards an in situ wedge developing Sunday so have continued to go below blended guidance for temperatures, keeping highs mostly in the 60s. There is some uncertainty as to whether or not this wedge breaks into Monday but typically see biases in models of breaking the wedge too early so for now have gone below blended guidance for highs Monday as well and kept at least low chances for rain. Beyond Monday, expect gradual warming trend through mid-week. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... VFR conditions generally expected through the 24hr TAF period. Satellite imagery shows higher clouds have almost cleared the area and skies should be mostly sunny through the day. Some possible MVFR/IFR vsbys through 13z at OGB but then VFR expected afterwards. Light and variable winds will pick up from the northwest to west at around 5 knots by 14z as a weak surface trough shifts southeastward through the area. Winds may shift back to the southwest by 20z in response to an approaching frontal boundary. EXTENDED AVIATION OUTLOOK...No significant impacts to aviation expected through Saturday. Restrictions expected on Sunday into Monday with possible developing wedge conditions. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$ ####018006090#### FXUS63 KGLD 181052 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 452 AM MDT Thu Apr 18 2024 .KEY MESSAGES... - Below normal temperatures are anticipated over the next few days. - Winter weather may return to portions of the area Friday night into Saturday, when rain could mix with, or transition to, wet snow. Light snow accumulation is possible especially in Yuma county(mainly on grassy and elevated surfaces). Significant impacts are not anticipated at this time. && .SHORT TERM /THROUGH SATURDAY NIGHT/... Issued at 330 AM MDT Thu Apr 18 2024 Across the Tri State region this morning, skies are cloudy as the area lies in between a strong surface ridge to the north and west, and a low/front over central/western portions of Kansas. A strong northerly gradient continues to move through the area with gusts still reaching the 35 to 50 mph range and temps as of 300 AM MDT ranging from the 30s west into the lower to mid 40s east. The main wx concerns for the short term period will initially focus on the strong northerly gradient over the cwa. Short term guidance does have the current speeds decreasing through the morning hrs from north to south as a strong ridge builds southeast into the central Plains. The result of the ridge building towards the central Plains is going to allow for the current northerly fetch to become more east-southeasterly. Short term guidance will have these winds persist into the first half of the weekend, setting the region up for the next wx concern. Next up, the result of the persistent E/SE upslope flow into the cwa will first be cloud cover to remain. There will be a couple weak shortwaves around 500/700 mb that will interact with the low level moisture to create showers. The latest CAMs(HRRR, RAP and NamNest) are showing precip to initiate in the northwest over Yuma county tonight into Friday morning, then eventually spread east and south through the day. Best chances for areal coverage precip will occur Friday night into Saturday morning as another shortwave moves off the Rockies through zonal flow aloft, before things taper down Saturday evening as the aforementioned ridge finally moves over the cwa. 20-30% chances for precip tonight and Friday do give way to 50-80% chances to end off the week. Friday night will have the highest pop chances. Colder air working into northern/ western locales will allow for a changeover to mainly snow showers, especially over Yuma county. Currently up to an inch is possible there, tapering to a half inch or less going east and south. Grassy/elevated surfaces will be most prone to any light accumulation, but current soil/road temps will aid in keeping amounts down for travel purposes. Some of the enhancement/changeover to light snow Friday night will/could be aided by a upslope effects of an 850mb low that pushes into the Colorado area. Strong ridging in that area may prevent a push towards the CO/KS border. If it does, the enhanced southeast flow at 850mb will help to continue/reinforce upslope moisture. For temps, daytime highs today will range widely with upper 40s in the west increasing to the upper 50s along/east of Highway 83. For Friday, 50s for most locales with some areas south of Highway 40 coming close to the 60F mark. Going into Saturday, mainly mid to upper 40s expected, with areas along/east of Highway 83 around the 50F mark. Overnight lows in the lower to mid 30s tonight, warmest east of Highway 25. Friday and Saturday nights, colder with a range from the upper 20s west into the mid 30s east. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... Issued at 1256 AM MDT Thu Apr 18 2024 The long term continues to favor a mix of near and below average temperatures and some precipitation chances. Sunday continues to favor dry and mild conditions on the back side of an upper shortwave. Highs are forecast to reach the 60's with winds out of the south. The rest of the week still has a fair amount of uncertainty due to the upper pattern. The overall pattern favors a disturbance moving through to begin the week, followed by some ridging, followed by a deeper disturbance later in the work week. The uncertainty lies in how deep/strong the features are and their timing. Generally, Monday is forecast to be near average with temperatures in the 70's and some chances for precipitation later in the day ahead of a potential shortwave. Tuesday would then be a bit cooler in the wake of the shortwave. Both days would have chances for precipitation. Wednesday would then be warmer with highs back towards 70 and generally dry conditions, though there could still be precipitation chances with no strong air mass change forecast (keeping moisture available over the area). Thursday would then be much warmer with ridging amplifying over the area as long as the next upper trough doesn't move through (ensemble spreads generally favor a end of the week passage of the next trough). Again this is just a general idea of next week as timing and magnitude of the features could still have a large impact on temperatures (most days have a 10-15 degree celsius spread in 850mb temp possibilities). && .AVIATION /12Z TAFS THROUGH 12Z FRIDAY/... Issued at 444 AM MDT Thu Apr 18 2024 For KGLD, increasing MVFR ceilings through about 19z, then turning VFR. Winds northerly 15-30kts through about 19z, then veering northeast around 10kts. By 07z Friday, southeast around 10kts. For KMCK, MVFR ceilings through about 14z-15z then becoming VFR. Winds, northerly around 20-30kts through 21z then dropping to about 10kts. By 04z Friday, light/variable. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...JN LONG TERM...KAK AVIATION...JN ####018008707#### FXUS61 KPHI 181052 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 652 AM EDT Thu Apr 18 2024 .SYNOPSIS... A stationary boundary will remain situated across the area today as weak low pressure meanders offshore. A cold front will pass through the region early on Saturday with high pressure building in its wake. High pressure will largely be in control through Tuesday before another chance of precipitation returns Tuesday night into Wednesday. && .NEAR TERM /THROUGH TONIGHT/... High pressure over Quebec and New England with ridging extending down into the northern Mid-Atlantic is associated with a stubborn, cool and stable airmass that will generally hold in place today and tonight. An occluding low pressure system tracking across the Great Lakes has been advecting warm air aloft over the cooler low-level air, but that low is beginning to transfer to a developing coastal low off the NJ coast this morning. That will only result in strengthening NE to N onshore flow in the boundary layer today. Even while some warmer air south of a stationary front has managed to creep into parts of the Delmarva, do not expect that air to make much progress northward. In many portions of our region, especially north and east of Trenton, temperatures will stay very steady through the day today, in the upper 40s and low 50s. While a mid- level shortwave is passing through early this morning, keeping the remnant of some fading convection alive in the form of a few light showers, expect those to continue to fade while lifting across northern NJ. Drizzle may be the predominant form of precipitation across portions of the NJ shore, northern NJ, and some of the ridges across SE PA this morning, perhaps even lingering into this afternoon. That will be accompanied by some areas of fog this morning, though that should not be dense outside of the Pocono Plateau and adjacent ridge-lines. This drizzle should not result in too much in the way of rainfall; likely less than 5 hundredths of an inch today. Other areas, particularly into the lower Delaware Valley southward, should stay mainly dry today. A raw northeast breeze will add to the very un-spring- like feel today, especially along the shore. Southern Delaware may still manage to hit 70F, especially with any breaks of sun, but that will be the exception in our area. Tonight may still see a little patchy, mainly toward the northern NJ shore, but overall expect dry conditions elsewhere, with overcast skies, and easing northeast winds. Would not totally rule out some patchy fog at times tonight into early Friday morning, but expect just overcast skies in most locations. Low temperatures will be several degrees cooler than the previous night in most spots; mainly in the low to mid 40s. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... Continued cloudiness and cool conditions will persist through Friday as the area remains wedged between a meandering low offshore and cold front approaching from the west. High pressure to the north and east looks to stay long enough that most of Friday should be dry, although rain chances will increase later in the day and peak on Friday night as the cold front passes through. Overall, PoPs on Friday night will be between 20-40%, with greater chances further west as atmospheric profiles are drier to the east. Temps on Friday will be mostly in the 50s to around 60, with lows in the 40s to near 50 on Friday night. Following the frontal passage, Canadian high pressure will drop south into the High Plains on Saturday, while nosing its ridge axis across the Eastern US. Other than some lingering showers early on Saturday, most of the day will be dry with clearing skies. Despite the frontal passage, the front really lacks any surge of "cold" air. So, while drier air pushes into the region, temps will actually be quite mild on Saturday as our boundary layer looks to be very-well mixed with 850mb temps near 5-6C. Bringing this down to the surface dry adiabatically, should result in highs at the surface in the mid to upper 60s, possibly reaching 70 degrees in some spots. Mostly clear skies and dry conditions will continue through Saturday night with lows in the upper 30s to mid 40s. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... For the most part, the long term period will generally be tranquil and quite seasonable, but will have to monitor a couple disturbances along the way. On Sunday and into Sunday night, will have to monitor the potential for some showers to our south. This will be associated with a stalled boundary sitting off the Southeast coast where a weak area of low pressure develops along it before skirting out to sea. Overall, any chance of showers looks to be minimal (up to a 30% chance), and only as far north as Cape May at this time. The remainder of the area will be dry despite increasing cloudiness. High pressure then firmly remains in control on Monday and into Tuesday. After this time, will have to watch back to the west as a cold front will be approaching during the Tuesday night into Wednesday timeframe. This is likely the next chance for some widespread showers to occur across the area. In terms of temperatures, we look to remain remain quite seasonable through the middle of next week. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas... Today...LIFR ceilings and IFR/MVFR VSBY for much of the region with light mist or fog this morning. Both CIGs and VSBYs should gradually lift heading into this afternoon, but the timing and extent of improvement is not certain. Some drizzle may be present early this morning, especially N and E of TTN. Winds mainly NE 6-12 kt, but stronger and gusty along the NJ shore. Low confidence in CIGs/VSBY today. Tonight...Ceilings around 010 this evening may drop back into the IFR category at times, but the overall forecast is for MVFR ceilings to hold steady or even improve somewhat toward Friday morning. VSBY mainly unrestricted, but would not rule out some MVFR light mist or fog in the evening. Winds mainly NE 4-8 kt. Low confidence. Outlook... Friday through Friday night...Sub-VFR likely with periods of low clouds with rain showers especially during Friday night. SE winds around 5-10 kt during the day, becoming SW winds around 5 kt or less at night. Moderate confidence. Saturday through Monday night...VFR expected. Mostly clear skies on Saturday, mostly cloudy skies on Sunday, and clear skies returning on Monday. W-NW winds expected through the period. High confidence. Tuesday...VFR early with sub-VFR possible late with rain showers. S winds. Low confidence. && .MARINE... Low pressure developing off the mid-Atlantic coast today, combined with high pressure still holding across New England will result in a tightening pressure gradient and increasing NE/N winds expanding down the NJ coast, eventually reaching Delaware by this evening. Those winds will peak with 25-30 kt gusts, prompting Small Craft Advisories over all our ocean zones, while seas build to 5-7 ft. As the low pressure system pulls away tonight, NE winds will gradually ease toward 15 kt, but seas will linger above 5 or 6 ft into Friday morning. Outlook... Friday through Friday night...The Small Craft Advisory is now in effect for all ocean waters through 6 PM Friday due to seas around 5 feet. Seas may linger above SCA criteria into Friday night with a chance for showers. No headlines are in effect for the Delaware Bay. Saturday through Tuesday...Other than some showers possible on Saturday, fair weather is anticipated. No marine headlines are expected. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory until 6 PM EDT Friday for ANZ450. Small Craft Advisory from noon today to 6 PM EDT Friday for ANZ451. Small Craft Advisory from 3 PM this afternoon to 6 PM EDT Friday for ANZ452-453. Small Craft Advisory from 6 PM this evening to 6 PM EDT Friday for ANZ454-455. && $$ SYNOPSIS...DeSilva NEAR TERM...Dodd SHORT TERM...DeSilva LONG TERM...DeSilva AVIATION...Dodd/DeSilva MARINE...Dodd/DeSilva ####018004398#### FXUS61 KRNK 181054 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 654 AM EDT Thu Apr 18 2024 .SYNOPSIS... A dry day is expected today with northwesterly winds. A much stronger front will cross our area Friday bringing some showers and storms, then cooler weather arrives for the weekend. && .NEAR TERM /THROUGH TONIGHT/... As of 245 AM EDT Thursday... Key Message: 1. Dry, warm, and breezy. A few showers still remain across the West Virginia mountains, but these will continue to decrease over the next few hours. Winds will gust up to 25 mph along the higher elevations today. Temperatures are expected to remain above normal with lows ranging from the lower 50s to the lower 60s, but highs should climb into the mid/upper 70s for the mountains and low/mid 80s for the Piedmont. Dewpoints will also fall into the upper 30s to the mid 40s by this afternoon, which will push relative humidities below 30 percent at most locations. Winds quickly diminish around sunset and winds overnight should be nearly calm. Could potentially have some spots into the 40s tonight if skies can remain clear to allow for radiational cooling. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 400 AM EDT Thursday... Key Messages: 1: Showers and storms Friday 2: A few showers possible in northern NC Saturday Low pressure and a cold front will transit the OH Valley and then stall near the Carolinas on Friday. On Friday this will result in showers beginning in the late morning, with some thunderstorms possible through the late afternoon. This front will settle just south of our area in the Carolinas, and a slowly approaching gradient of higher pressure will dry out any precip by Friday night. On Saturday, most of the area will be free of rain with the exception of isolated showers in northern NC Saturday afternoon. The continued increase in surface pressure from the west will suppress rain potential further north of the front in VA and WV. Temperatures will cool a bit with the front and more showers. Expect temps in the 60s and low 70s. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 420 AM EDT Thursday... Key Messages: 1: Rain chances Sunday and Wednesday 2: Cooler than normal temperatures Sunday and Monday, rebounding on Tuesday Behind a cold front that moves offshore Saturday night, cooler than normal temperatures can be expected Sunday and Monday. A disturbance in eastern Texas will track across the Deep South Saturday, then move off the Carolina Coast Sunday night. The northern edge of the rain shield is expected to reach the Highway 460 corridor Sunday afternoon, then exit the Piedmont around midnight, ushered out quickly by a fast moving area of weak high pressure. Surface high pressure over the region Monday and Tuesday will allow temperatures to return to near normal levels and provide for calm weather. Showers reenter the area Wednesday as another cold front tracks over the region. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... As of 645 AM EDT Thursday... Some MVFR cloudiness this morning across the mountains as a passage of a decaying front moves through. MVFR will linger for perhaps an hour or two, but then should see widespread VFR for the remainder of the TAF period as skies become clear. Winds will be on the increase today, gusty from the northwest. Could see some gusts to 20kt to perhaps 25kts in the mountains. Winds quickly diminish by sunset and will be light/calm tonight. Extended Aviation Outlook... VFR conditions are expected into early Friday. However, a cold front will cross the area by late Friday with scattered showers and thunderstorms possible. The cold front will exit eastward by Saturday, but some MVFR ceilings may linger in the mountains through the morning. North winds will provide some clearing for late Saturday, but more moisture may surge northeastward during Sunday and Monday to bring another chance of rain. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...BMG NEAR TERM...BMG SHORT TERM...VFJ LONG TERM...RCS/VFJ AVIATION...BMG