####018009510#### FXUS61 KAKQ 200703 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 303 AM EDT Tue May 20 2025 .SYNOPSIS... High pressure builds north of the area tonight, keeping dry conditions across the local area through most of Tuesday. Temperatures cool down, and conditions become unsettled late Tuesday through Thursday as low pressure tracks towards and crosses the local area. Dry and cool conditions return for the Memorial Day weekend. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... As of 820 PM EDT Monday... Key Messages: - Dry and cooler tonight with decreasing clouds overnight. The latest WX analysis shows a weak sfc trough passing through the CWA, with a NW flow aloft. High clouds have thickened up as a result, but conditions remain dry. Strong sfc high pressure is centered near Hudson Bay Canada (nearly 1040 mb), and will ridge south into the northern mid-Atlantic overnight. Northerly winds will become a little elevated near the coast as cooler air moves over the Bay, with winds farther inland generally 5-10 mph or less. The sky will become mostly clear overnight, and with lighter winds inland, expect lows to fall into the low-mid 50s across interior portions of the FA, with a few upper 40s possible in the piedmont. Near the coast, lows will average in the upper 50s to lower 60s. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... As of 309 PM EDT Monday... Key Messages: - The next system approaches Tuesday with unsettled conditions expected Tuesday night and Wednesday. - There is a Marginal Excessive Rainfall Outlook for much of the area Tuesday night into early Wednesday morning. - Showers and storms continue into Wednesday afternoon, with localized strong to severe storms possible, especially south. The drier airmass will slowly start to be replaced by a more moist airmass on Tuesday and cloud coverage will increase through the day from west to east. This will occur as an area of low pressure approaches from the west. This low will be the instigator of our next round of strong to severe storms, as well as possible isolated instances of flash flooding early Wednesday through early Thursday. With the increasing cloud cover, high temperatures will be capped in the 70s Tuesday. Precipitation will start to move in from the west to east late Tuesday night, but due to the drier airmass initially in place ahead of the more robust moisture, some overrunning may take place. Once the drier air is replaced, heavier rainfall is expected late Tuesday night generally after midnight through the morning. Rainfall accumulations could reach up to an inch in some locations, with isolated higher amounts not out of the realm of possibilities. WPC has placed most of the forecast area in a Marginal Risk for excessive rainfall for Tuesday night due to the potential for localized flash flooding, especially in urban or poor drainage areas. Due to the lack of instability, have left thunder out of the forecast Tuesday night through Wednesday morning. After the initial round of rainfall moves through, there will likely be a lull followed by redevelopment after the atmosphere recharges for a bit. By Wednesday afternoon, deep shear values will increase to near 50 kts. Instability is expected to increase across mainly the southern portion of the forecast area during peak heating in the afternoon, so a few strong to severe storms cannot be ruled out through the evening, though it is more of a conditional threat that hinges upon how far the warm front can lift northwards. The farther northward the warm front lifts, the broader the geographical extent the instability can reach. As of now, model guidance is suggesting that the northern extent of instability will reach roughly the VA/NC border. This will also play a part in the high temperatures Wednesday, with likely a sharp gradient between the north and south of the front. Currently, most of the area has been placed in a Marginal Risk for severe weather as models come into agreement as to where the front reaches Wednesday. We will continue to monitor any trends and adjust the forecast as necessary. Convection will taper off from west to east Wednesday evening into the overnight hours. && .LONG TERM /THURSDAY THROUGH MONDAY/... As of 309 PM EDT Monday... Key Messages: - Chance for showers lingers across the N Thursday. - Below average temperatures are expected late this week into next weekend. - Another storm system potentially approaches Memorial Day or overnight. The low off of the Mid-Atlantic coast will continue to lift northeastward and strengthen. Another weaker low pressure will track through the Ohio River Valley area northeast towards the eastern Great Lakes area Wednesday through Thursday. There is a little bit of discrepancy in the global models as to what becomes of this low and its upper trough counterpart, but regardless of the outcome, chance PoPs will likely linger into Thursday. The best chance for showers will be across the northern half of the forecast area Thursday afternoon due to the combination of the low deepening off the coast and the low near the eastern Great Lakes. One of the main differences in the synoptic set up will be the high temperatures in the latter half of the week. Have kept temperatures a few degrees below normal Thursday through the weekend, with highs in the 70s and lows dropping into the 40s to 50s so a chillier, albeit dry and partly cloudy to mostly sunny, Memorial Day weekend is on tap for the area. Another storm system may try to approach the region during the day on Memorial Day or overnight, but confidence in timing is low at this range of the forecast. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... As of 215 AM EDT Tuesday... VFR conditions will prevail through the 06z/20 TAF period at all terminals. SCT high clouds over the area this morning into this afternoon. Clouds thicken and gradually lower later this afternoon into this evening ahead of our next weather system (but remain VFR). Light rain showers will be possible at RIC late in the forecast period (after ~03z) with the remainder of the sites staying dry through 06z Wed. N to NE winds prevail this morning into this afternoon, becoming E late in the day. Outlook: Rain chances increase significantly Tuesday night, and widespread rain is expected later Tuesday night through most of Wednesday, with flight restrictions likely. E-SE winds of 10-20 kt (highest near the coast) are expected Wednesday. Mainly VFR Thursday but scattered aftn showers are possible. Dry/VFR Fri- Sat. && .MARINE... As of 305 AM EDT Monday... Key Messages... - Small Craft Advisories continue for the Chesapeake Bay through early this morning morning for elevated northerly winds. - Low pressure impacts the region Wednesday into Thursday, with elevated winds and waves/seas likely. Local waters are sandwiched between two areas of low pressure this morning: a stronger low off the coast of Nova Scotia and a weaker low near the southern waters. NNE winds are ~15kt with gusts to ~20kt over the bay and coastal waters, 10-15kt over the rivers/Currituck Sound. Buoy obs indicate seas of 2-3ft; waves are also around 2ft. SCAs are in place through 7am. Winds will diminish early this morning as both areas of low pressure push further offshore and the pressure gradient weakens locally. Then expecting benign marine conditions with N winds of 5-10kt through the evening. Winds then turn onshore for tonight. Seas remain at 2-3ft through this evening. SE winds will increase late tonight as a warm front lifts N toward the VA/NC border and an area of low pressure passing through the region along it. By early Wed morning, expecting SE winds to be up to 20-25kt (15-20kt for upper rivers/Currituck Sound). SCAs will be needed starting late tonight/early Wed, but will hold off for this cycle given the SCAs already in place this morning. Elevated onshore winds will continue through the day Wed, then diminish Wed night to ~15kt as winds turn to the NW behind the low pressure. Seas/waves will build to 4-5ft for all coastal waters and the lower bay Wed morning. Waves elsewhere will be 2-3ft. Onshore winds will remain stronger for longer N of Cape Charles on Wed, so seas in northern waters will build to 5-7ft by the evening. Gusty westerly winds of 15-20kt are then expected during the day Thursday and into Thurs night as a secondary cold front or two make their way across the region. The offshore winds help seas drop back to 4-5ft by Thurs morning. Seas look to drop below 5ft no later than Fri morning as the offshore winds diminish to under 15kt. Breezy, but sub-SCA, conditions then expected for Friday. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 7 AM EDT this morning for ANZ630>632-634. && $$ SYNOPSIS...LKB NEAR TERM...LKB/NB SHORT TERM...AJB/NB LONG TERM...AJB/NB AVIATION...AJB MARINE...AC