####018008794#### FXUS61 KLWX 260122 CCA AFDLWX Area Forecast Discussion...CORRECTED National Weather Service Baltimore MD/Washington DC 922 PM EDT Thu Apr 25 2024 .SYNOPSIS... High pressure wedges its way south along the eastern Appalachians tonight into Saturday. Cooler temperatures will prevail as a result along with increased cloud cover. A warm front lifts through the area this weekend bringing a significant warm up Sunday and Monday. The next chance for widespread precipitation arrives with a cold front Tuesday into Wednesday next week. && .NEAR TERM /THROUGH TONIGHT/... Cloud cover will remain prevalent tonight as onshore easterly flow increases with high pressure wedging south from the eastern Great Lakes region. However, some clearing is likely especially along the PA/MD border and back across central/northeast MD. These areas do have the potential to see a little frost with overnight lows in the mid to upper 30s. Confidence is moderate given the extent of the cloud cover and clearing along the periphery of the wedge. For that reason, have went ahead with a Frost Advisory for Cecil, Harford, Carroll, and northern Baltimore counties in Maryland where better clearing looks to take place. Temperatures in these locations will run 34 to 37 degrees. Elsewhere lows are expected to remain in the upper 30s and low 40s especially where low and mid level (stratus) clouds look to hang on. Some patchy drizzle is even possible by daybreak Friday morning along the crest of the Blue Ridge and eastern slopes of the Alleghenies as moisture increases on southeast flow. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... High pressure over the New England states will remain wedged along the eastern slopes of Alleghenies and Blue Ridge heading into the start of the weekend. This will result in continued cloudiness at times along with near normal to slightly below normal temperatures. Highs Friday will push back into the low to mid 60s with 50s over the mountains. Overnight lows Friday will fall back into the low to mid 40s. By Saturday, surface high pressure will continue to nudge south and east off the southern New England coast into the western Atlantic for the start of the weekend. Meanwhile, at the surface a warm front will lift north along the western periphery of the surface high and push toward the eastern Great Lakes Saturday into Sunday. This front may lend to a few showers mainly along and west of the Blue Ridge although moisture should remain limited with upper level ridging quickly building in from the southeastern U.S. High temperatures Saturday will range from the upper 50s and low 60s north of I-66/US- 50 with mid to upper 60s further south. This spread is due largely in part to the placement of the warm front, widespread cloud cover, and rain chances across portions of the region. The wedge finally breaks Saturday night and into the day Sunday as strong upper level ridging builds in from south and surface high pressure sits off the NC coast. This will send an ample supply of warm air advection over the region yielding a Summertime feel for the last weekend of April 2024. Lows Saturday night will fall in the upper 40s and low to mid 50s. Conditions will remain dry with skies gradually clearing daybreak Sunday morning. && .LONG TERM /SUNDAY THROUGH THURSDAY/... A strong upper-level ridge will build over the region Sunday before reaching its peak intensity on Monday. This will lead to well above average temperatures, with some areas potentially pushing 90 on Monday along the I-95 corridor. A weakening upper trough will lift to our northwest on Tuesday as it ejects out of the central CONUS into the Great Lakes region. A weak piece of shortwave energy breaks off as this happens and slides across our region. An accompanying "cold front" will push through and perhaps pop off some thunderstorms during the afternoon/evening hours. There should be enough instability and some decent wind shear aloft to produce some strong to severe thunderstorms as well. The amount of instability is still a bit in question however, as this system doesn't have a strong link to the Gulf of Mexico moisture source, thus keeping dew points down into the upper 50s to low 60s. Given that this is day 6 at this point, lots of time for things to change, so stay tuned to the latest forecast each day. Showers and a few storms possible again on Wednesday with an even weaker shortwave traversing the region. Not much relief from the heat from the previous front, as highs remain in the mid 80s. && .AVIATION /01Z FRIDAY THROUGH TUESDAY/... Predominantly VFR conditions are expected through the valid TAF period. A brief period of patchy drizzle/fog could effect KCHO/KMRB late tonight into early Friday morning reducing cigs/vsbys into the MVFR to IFR categories. Winds will remain light out of the east and northeast running 5-10 kts through this evening before becoming light and variable overnight. Overall cigs will remain BKN-OVC across the terminals through Friday with high pressure over New England wedging south east of Alleghenies and Blue Ridge. Highest cloud coverage will be confined to terminals south and west of corridor with more clearing within the corridor and north/east late tonight into Friday. VFR conditions will prevail during this time although cloud cover will fill back in at all TAF terminals late Friday evening and into the day Saturday as a warm front lifts through the region. This front will provide a few spotty low end VFR to high end MVFR showers to terminals along and west of the Blue Ridge. It will also bring a change and increase in the wind from the southeast Friday to the south Saturday ushering in warmer conditions. Gusts of 20 to 25 kts can be expected Saturday as the front passes through. Southerly winds will remain elevated Sunday and Monday although gust will remain below 20 kts. VFR conditions are expected with a strong upper level ridge overhead. A potent upper-level ridge will keep things quiet through Monday with VFR conditions expected. A cold front will approach the area Tuesday bringing the potential for sub-VFR showers and thunderstorms. && .MARINE... As of 2100 LT, east to southeast winds are periodically gusting 15 to 18 knots along the Chesapeake Bay and portions of the Tidal Potomac. Occasional gusts to near 20 knots are possible through this evening with winds diminishing in the next two hours. Sub-SCA level southeasterly winds are expected Friday although channeling remains possible late in the afternoon and evening hours. Winds could flirt with SCA criteria for a few hours on both Saturday and Sunday. A warm front will lift across the waters Saturday changing the winds toward more of a southerly direction. With surface high pressure off the Carolina coast expected, southerly winds Saturday to change to more of a south/southwesterly direction Sunday. Gusts of 15-20kts are expected Saturday with 20-25 kts gusts possible Sunday due to southerly channeling. Surface high pressure offshore will bring a southerly flow to the region, which could channel up the Chesapeake Bay at times. This could necessitate SCAs through Monday. && .TIDES/COASTAL FLOODING... Coastal Flood Advisories are in effect for Annapolis, Straits Points, and DC SW Waterfront for the Friday AM high tide. Near moderate coastal flooding is possible near Annapolis and Straits Point. Other spots could reach minor flood stage, which would require additional Coastal Flood Advisories. This is due in part to increased northeast to easterly flow eventually switching to the south/southeast this weekend. Additional periods of coastal flooding are likely over the weekend as southerly winds persist, and many locations approach or reach minor flood stage. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...Coastal Flood Advisory from 8 AM to 1 PM EDT Friday for DCZ001. MD...Frost Advisory from 2 AM to 8 AM EDT Friday for MDZ005-006-008- 507-508. Coastal Flood Advisory from 2 AM to noon EDT Friday for MDZ014. Coastal Flood Advisory from midnight tonight to 7 AM EDT Friday for MDZ017. VA...None. WV...None. MARINE...None. && $$ SYNOPSIS...AVS/EST NEAR TERM...AVS/EST SHORT TERM...EST LONG TERM...CJL AVIATION...AVS/CJL/EST MARINE...AVS/CJL/EST TIDES/COASTAL FLOODING...EST/KRR/DHOF