Area Forecast Discussion
Issued by NWS Sterling, VA

Home |  Current Version |  Previous Version |  Graphics & Text |  Print | Product List |  Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
559 FXUS61 KLWX 300105 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 905 PM EDT Wed May 29 2024 .SYNOPSIS...
-- Changed Discussion --
High pressure will build in from the northwest behind the cold front that pushed through earlier this evening. High pressure remains overhead throughout the weekend before pushing east at the start of the workweek.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
The cold front that caused some thunderstorms earlier this evening has now mostly pushed through the region. A potent piece of shortwave energy continues to push through in the wake of this front, thus popping off a few showers over western areas this evening still. As dry air spills in however, showers will quickly die off overnight, giving way to mostly clear skies by the overnight hours for most areas, aside from those along/west of the Allegheny Front. Low temperatures will drop again into the low to mid 50s.
-- End Changed Discussion --
&& .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... The aforementioned upper level trough will continue pivoting and deepening over the east coast throughout the day on Thursday. A dry airmass in place will keep any widespread precipitation at bay, but the disturbance moving overhead will result in some clouds over the region. In addition to some clouds, a stray rain shower cannot be ruled out, mainly in the southern portions of the forecast area. The upper level trough will exit the region overnight Thursday into Friday morning, with ridging moving in behind it. At the surface, high pressure will build in from the Great Lakes beginning Friday as the upper level trough moves off shore. Cloud cover will decrease Thursday night into Friday with sunny skies and dry conditions expected during the day. Dry air aloft will have dewpoints in the 30s to 40s, yielding seasonably cool temperatures. There will be a temperature gradient on both Thursday with highs in the low 60s for those at higher elevations while those in the southern potions of the forecast area and in the metros are in the upper 70s. Temperatures moderate slightly on Friday with temperatures ranging from mid 60s to mid 70s across the area dependent on elevation. Clear skies and light winds will provide favorable conditions for radiational cooling each night. Overnight lows on Thursday will dip into the 40s along and west of the Blue Ridge with those east of the Blue Ridge staying in the 50s. Some locations along the Alleghenies could even drop into the 30s with a potential for some frost. Overnight lows on Friday will be just a few degrees warmer with temps in the 40s-50s. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Quiet weather conditions look to continue into the first half of the weekend with low pressure over eastern Canada drifting east and high pressure overhead. Overall flow will remain fairly zonal throughout the weekend which will allow for a slow return of low level moisture and shortwave disturbances heading into early next week. Saturday, will be the pick of the weekend with high pressure nearly overhead. Mostly sunny skies are expected with high temperatures in the upper 70s and low 80s. High pressure will slowly push off the southeast U.S coast Saturday night into Sunday allowing for an uptick humidity and cloud cover. Skies will turn mostly clear to partly cloudy with lows in the upper 40s and low to mid 50s. By Sunday, high pressure centers itself off the southeast U.S coast. This will lead to a return of low level moisture in form of increased humidity as well as the risk for a few thunderstorms along and west of the Blue Ridge as shortwave energy pushes east from the Midwest region. Better chances for showers and thunderstorms exists during the afternoon and evening hours Monday and Tuesday areawide as additional pieces of shortwave energy pivot through. Rainfall amounts are expected to be light at this point and no severe weather is anticipated at this point.Neither SPC nor WPC have highlighted any threats over the region for the period at this time. Even with that said, CSU Learning Machine Probabilities and CIPS analogues continue to point toward stronger storms during the Tuesday and Wednesday time. This is in association with a cold front that will slowly progress eastward by the middle and latter half of next week. We will continue to monitor this threat over the next several days. Temperatures will creep back above normal Monday through Wednesday next week. Highs will warm back into the mid to upper 80s and perhaps low 90s with 850 mb temperatures running +12 to +16 degrees Overnight lows will return to the mid to upper 50s and low 60s. && .AVIATION /01Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
As showers have dwindled this evening, VFR conditions returned to all terminals, which could continue tonight. VFR conditions are expected Saturday and Sunday with high pressure nearby. A slight chance for a few thunderstorms is possible mainly at terminals along and west of a line from KMRB down to KCHO. Some restrictions are possible in and around any thunderstorm activity that may form. Higher chances for more widespread restrictions from shower and thunderstorm activity are possible Monday through Wednesday as multiple pieces of shortwave energy push through.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
Northwesterly winds pick up in the wake of the cold front that pushed through earlier, thus necessitating SCAs to be issued starting just after midnight and continuing through Thursday. North/northwesterly flow should be below SCA criteria on Friday, with dry conditions expected across all waters. Sub-SCA level winds are expected Saturday and Sunday. Winds will be calm to variable Saturday with high pressure overhead. South to southeasterly winds return Sunday as high pressure pushes off the southeast U.S coast. An isolated shower or thunderstorm cannot be ruled out due to the bay breeze Sunday afternoon/evening. Better chances for showers and thunderstorms exists Monday through Wednesday as multiple disturbances pass through.
-- End Changed Discussion --
&& .LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory from 2 AM to 5 PM EDT Thursday for ANZ530>534-536-537-539>541-543. Small Craft Advisory from 7 AM to 5 PM EDT Thursday for ANZ535- 538-542.
-- End Changed Discussion --
&& $$ SYNOPSIS...AVS NEAR TERM...AVS/CJL SHORT TERM...AVS LONG TERM...EST AVIATION...AVS/CJL/EST MARINE...AVS/CJL/EST