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Show Area Forecast Discussion - Norfolk - Wakefield, VA (Hampton Roads/Tidewater/Virginia Beach, VA Area) Selection: |
| #1209042 (Received by flhurricane at: 4:24 AM 21.Nov.2024) AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 419 AM EST Thu Nov 21 2024 .SYNOPSIS... Low pressure will push offshore of the Delmarva coast early this morning. Meanwhile, several disturbances drop across the area over the next couple of days, bringing a prolonged period of gusty winds and chilly temperatures. Weak high pressure builds over the area late in the weekend, bringing a gradual warmup for the first half of next week. && .NEAR TERM /THROUGH TONIGHT/... As of 410 AM EST Thursday... Key Messages... - Blustery and much cooler weather conditions behind a strong cold front. NW winds average 15-20 mph with gusts to 25 to 30 mph (highest coastal areas). - Remaining mainly dry, aside from a few showers over the northern neck and the eastern shore. - A Freeze Watch has been issued for Thursday night over interior northeast NC and portions of the western Tidewater area. Latest analysis reveals a potent upper level low centered over the Great Lakes early this morning. At the surface, a strong ~996mb sfc low was analyzed over the upper peninsula of Michigan, with a secondary low now just offshore of the Delmarva coast. The strong trough and its associated sfc low will pivot SSE into the northern mid-Atlantic through tonight. This allows the area to start drying out today on breezy NNW winds. There will be multiple shortwaves transversing SE along the trough, thereby allowing multiple reinforcing shots of cooler air. The first (and weakest) of these shortwaves push through this afternoon and this evening. This will result in another surge of gusty winds to 20 to 30 mph, some clouds and perhaps a few showers along the eastern shore. Otherwise, expect most of the area to remain dry today. Highs only top out in the low to mid 50s. Winds do decouple a bit inland later Thu night, which will make for a stark temperature contrast between inland areas and the coast. Look for lows in the upper 20s to low 30s inland, with mid to upper 30s along the coast. This will put a narrow stripe of counties still active in the frost freeze program with lows right around freezing. Have gone ahead and added these counties from Bertie/Northampton and Gates NC up to James City in a Freeze watch for tonight. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 410 AM EST Thursday... Key Messages... - Another disturbance dropping across the region will provide another day of gusty winds, and increasing clouds for Friday. - More widespread showers are possible on Friday. A few instances of graupel or even some wet snowflakes are possible over northern portions of the area Friday morning into early afternoon. The second shortwave comes Friday and looks to be a bit stronger/cooler with highs in the mid upper 40s across the Piedmont and lower 50s along the SE coast. The latest models depict the core of the upper low across eastern PA and NJ pivoting up into New England, with a rather strong shortwave diving SE across local area. Have increased PoPs into likely range for the northern neck and eastern shore for showers from midday Friday into Friday night. Have also included some low end PoPs for along and to the S of the I-64 corridor into RIC metro and Hampton Roads. Given the relatively shallow moisture layer between 850-700 mb farther south, would expect minimal QPF. However,a good portion of that moisture layer is within the DGZ and could easily result in some graupel or even a few snowflakes mixing in over northern portions of the area Friday morning into the early afternoon. Ground temperatures would be much too warm for any impacts, but certainly a sharp contrast from just a few days ago. Drying out Friday evening/night, but remaining breezy and partly to mostly cloudy with low temperatures not quite as cold in the upper 30s and lower 40s. The upper level trough will begin to move out of the area into the Gulf of Maine Saturday, as upper ridging builds to the east. This will allow a milder day with highs warming back into the middle 50s to around 60. The breezy conditions gradually relax late Saturday into Sunday as the trough moves out of the region. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 410 AM EST Thursday... Key Messages... - High pressure moves back in bringing dry weather back across the region over the weekend into early next week. Temperatures next week are expected gradually moderate each day through midweek, as the high moves off the coast and upper ridging crests overhead Monday and Tuesday. Highs warming back into the upper 50s to around 60s on Monday, with highs in the lower 60s by midweek. Early morning lows warm back into the 40s Tuesday and Wednesday mornings. Rain chances return to the forecast next Wednesday ahead of the next system arriving from the NW. Will note, by the middle of next week the ensembles do disagree with the placement and strength of the next system. However, they do agree on a potential system and Pops remain tn the forecast and stay between 15-25%. The surface low slowly shifts into the Gulf of Main on Saturday afternoon and night. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... As of 140 AM EST Thursday... The well-advertised strong cold front swept across the region earlier this morning, bringing gusty winds, showers and variable CIGs to area terminals. Conditions continue to gradually improve in the wake of the front, with a gradually clearing sky expected over the next few hours. CIGs have already returned to VFR inland, with MVFR lingering along the immediate coast from ECG to SBY through 07-09z/2-4 AM EST before returning to VFR. NW winds will average 10-15 kt through around and just after sunrise, then increase and shift to the W at 15-18 kt with gusts to around 25 kt from late morning through early evening. Increasing aftn clouds are expected, but CIGs should remain VFR, averaging 6-8 Kft AGL. Outlook: Gusty W-NW winds continue Fri-Sat, with less wind by Sunday. Scattered to numerous showers and flight restrictions are expected across N/NE sections of the area Friday aftn/Fri night. && .MARINE... As of 410 AM EST Thursday... Key Messages: - Gale Warnings remains in effect early this morning for the Chesapeake Bay, Lower James River, and coastal waters. - Winds remain elevated through Saturday night. - Another period of Gale conditions is increasingly likely late Friday afternoon through Friday night. Early morning surface analysis depicted a cold front E of the local waters with an occluded low over the Great Lakes and a secondary low off the Mid Atlantic coast. Winds were NW 25-30 kt with gusts up to 40 kt across the Ches Bay, coastal waters, and Lower James River. As such, Gale Warnings remain in effect until 7 AM for these areas. Winds have diminished to SCA level across the upper rivers and Currituck Sound where Gale Warnings have been replaced with SCAs. Winds gradually diminish this morning as the pressure gradient weakens, eventually becoming W this afternoon. A period of potentially sub-SCA conditions is possible across the upper rivers and Currituck Sound later this morning into this afternoon with W winds 15-20 kt with gusts up to 25 kt across the Ches Bay and southern coastal waters. However, W winds increase back to 20-25 kt with gusts up to 30 kt late this afternoon into tonight behind a secondary cold front. A few gusts up to 35 kt are possible across the coastal waters and lower bay with this surge, however, wind probs for gusts of 34 kt are <40% (lower for zonal averages). Additionally, the surge looks to be brief (~3 hrs). As such, will refrain from issuing Gale Warnings for this surge at this time. Winds remain elevated (although trending lower) into Fri before a trough moves through, reinforcing the CAA yet again. Wind probs for 34 kt gusts are high for this surge with probs approaching 100% across the coastal waters and 70% across the Ches Bay. As such, expect W winds to increase to 25-30 kt with gusts up to 40 kt across all local waters late Fri afternoon through Fri night. While chances for Gale conditions late Fri into Fri night are high, will hold off on Gale Watches for now given ongoing Gale Warnings across the same zones for this morning`s surge. However, Gale Watches for late Fri into Fri night will be needed once current Gale Warnings are allowed to expire. SCA conditions continue Sat before winds gradually diminish Sat night into Sun as high pressure builds in. Waves and seas of 3-5 ft and 4-6 ft (locally higher possible) respectively continue to be possible early this morning. Waves subside to 2-4 ft later this morning with seas remaining elevated into Sat night. Another period of 4-5 ft waves is possible with the Fri afternoon into night surge. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...Freeze Watch from late tonight through Friday morning for NCZ012>014-030. VA...Freeze Watch from late tonight through Friday morning for VAZ089-090-092-093-096. MARINE...Gale Warning until 7 AM EST this morning for ANZ630>632-634- 638-650-652-654-656-658. Small Craft Advisory until 6 AM EST Saturday for ANZ633- 635>637. && $$ |
| #1209032 (Received by flhurricane at: 1:54 AM 21.Nov.2024) AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 143 AM EST Thu Nov 21 2024 .SYNOPSIS... A strong cold front moves across the area late tonight into Thursday, bringing colder, drier air and blustery NW winds through the late week period into the upcoming weekend. High pressure will build back into the region by the end of this weekend keeping the region dry. && .NEAR TERM /UNTIL 7 AM THIS MORNING/... As of 730 PM EST Wednesday... Key Messages... - A strong cold front moves across the region tonight into Thursday morning. Showers with a few embedded tstms prevail this evening, lingering into early morning to the E. - Strong, gusty NW winds develop post-frontal, with gusts up to 30-40 mph (locally higher across the eastern shore where a Wind Advisory is in effect). The latest analysis indicates the sfc cold front located along a line from near LKU to DAN, with strong gusty NW winds immediately in the wake of the boundary. Showers have been most prevalent across NW and SE portions of the FA, with the coverage more scattered across central VA. Elevated tstms are primarily located over N-NW portions of the CWA. It remains very warm for a late November evening, with temperature as of 8 PM still mainly in the lower 60s. The timing of the front based on latest trends is for the wind shift to arrive between 9-10pm W of I-95, pushing to the coast between 11pm and 1 am. Immediately in the wake of the front, there will be a brief period of wind gusts between 30-40 kt across most of the area, with 35-45 kt across Delmarva. With decent model guidance a wind advisory is needed for the area. There is also the possibility of these wind gusts knocking down trees and branches across the region. These conditions will be brief and last between 1 to 3 hours. Once the frontal passage moves through these conditions will die down slightly but winds will still remain breezy until closer to sunrise when they diminish further. Skies are expected to clear and weather conditions will remain breezy behind the frontal passage. With these clearing skies and cooler and drier air being advected into the area, overnight low temperatures are expected to drop to the mid 30s to around 40F W of I-95, with 40-45F to the E. && .SHORT TERM /7 AM THIS MORNING THROUGH FRIDAY NIGHT/... As of 325 PM EST Wednesday... Key Messages... - Gusty NW winds continue Thursday and Thursday night. NW winds average 15-20 mph with gusts to 25 to 30 mph (highest coastal areas). - Blustery and much cooler weather conditions behind a strong cold front Thursday-Friday night. The strong trough will continue to hang around the area through the early portion of this weekend. This allows the area to start drying out Thursday with the persistent northwesterly flow. There will be multiple shortwaves transversing along the trough allowing multiple reinforcing shots of cooler air. The first of these push through Thursday evening, bringing additional gusty winds, some clouds and perhaps a few showers along the eastern shore. Otherwise expect most of the area to remain dry. Highs only top out in the 50s Thursday. Winds do decouple a bit inland later Thu night, which will make for a stark temperature contrast between inland areas and the coast. Look for lows in the upper 20s to low 30s inland, with mid to upper 30s along the coast. The second shot comes Friday and could potentially be cooler than Thursday with highs in the upper 40s across the Piedmont and lower 50s along the coast. The latest models depict the core of the upper low across eastern PA and NJ, with a rather strong shortwave diving SE across the eastern shore. Expect a good chance for showers Fri aftn into Fri night on the eastern shore, with much lower PoPs for light showers or just sprinkles more favored along and to the S of the I-64 corridor. With the additional cloud cover, Friday evening/night, low temperatures only cool down in the upper 30s and lower 40s. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... As of 325 PM EST Wednesday... Key Messages... - High pressure moves back in bringing dry weather back across the region over the weekend into early next week. Into the weekend and early next week the latest 20/12z ensemble guidance is in decent agreement with the synoptic pattern. The upper level trough will begin to move out of the area by saturday and sunday allowing a ridge to take its place. This will allow temperatures to warm up into the middle 50s to around 60. The breezy conditions will taper off late Saturday into Sunday as the trough moves out of the region. Temperatures next week are expected to warm a little next week as the high moves off the coast with highs warming back into the upper 50s to around 60s on Monday, with highs in the lower 60s by midweek. Early morning lows warm back into the 40s Tuesday and Wednesday mornings. Rain chances return to the forecast next Wednesday ahead of the next system arriving from the NW. Will note, by the middle of next week the ensembles do disagree with the placement and strength of the next system. However, they do agree on a potential system and Pops remain tn the forecast and stay between 15-25%. && .AVIATION /07Z THURSDAY THROUGH MONDAY/... As of 140 AM EST Thursday... The well-advertised strong cold front swept across the region earlier this morning, bringing gusty winds, showers and variable CIGs to area terminals. Conditions continue to gradually improve in the wake of the front, with a gradually clearing sky expected over the next few hours. CIGs have already returned to VFR inland, with MVFR lingering along the immediate coast from ECG to SBY through 07-09z/2-4 AM EST before returning to VFR. NW winds will average 10-15 kt through around and just after sunrise, then increase and shift to the W at 15-18 kt with gusts to around 25 kt from late morning through early evening. Increasing aftn clouds are expected, but CIGs should remain VFR, averaging 6-8 Kft AGL. Outlook: Gusty W-NW winds continue Fri-Sat, with less wind by Sunday. Scattered to numerous showers and flight restrictions are expected across N/NE sections of the area Friday aftn/Fri night. && .MARINE... As of 345 PM EST Wednesday... Key Messages: - A Gale Warning has been issued for all local waters tonight due to strong NW winds behind a cold front. - Another period of Gale conditions is increasingly likely Friday afternoon through Friday night. Current surface analysis shows high pressure well offshore the southeast coast and low pressure over the Great Lakes, with a stationary front draped across the area and a cold front dragged across Ohio to Georgia. Winds are generally SE around 5 kt becoming S 10-15 kt ahead of a strong cold front. This front will quickly push through the area tonight crossing coastal waters 10PM to 1AM Thursday. Confidence is strong in Gale force winds behind the front as cold air moves in behind the front. Winds will abruptly become NW 30-35 kt with gusts up to 50 kt across all coastal waters. As such, Gale Warnings have been issued across all waters beginning at 10PM tonight. The strong winds will quickly subside to 20-25 kt behind the initial surge. A short period of sub-SCA conditions is possible Thursday, but then winds will ramp back up to at least SCA conditions Thursday night with winds W at 25-30 kt with gusts up to 30 kt across all waters as a weak trough moves over the area. Winds will be sub-SCA conditions Friday, but a stronger trough will increase winds Friday night to W at 25-30 kt with gusts up to 35 kt in the Bay and 40 kt over the coastal waters. There is high probability (>80%) for wind gusts greater than 34 kt Friday night, but will wait for future model guidance to determine in Gale headlines are necessary for this surge. Winds will then remain sub- SCA conditions for the weekend and early next week. Waves and seas are currently 1-2 ft this afternoon and will increase behind the front to 3-5 ft tonight (locally higher is possible). Waves and seas will decrease Thursday to 2-4 ft in the Bay and 2-4 ft in the coastal waters. A ramp up along with the winds Friday is expected with waves 3-5 ft and seas 4-6 ft. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...Wind Advisory until 4 AM EST early this morning for MDZ021>025. NC...None. VA...Wind Advisory until 4 AM EST early this morning for VAZ099-100. MARINE...Gale Warning until 7 AM EST this morning for ANZ630>634-638- 650-652-654-656-658. Gale Warning until 4 AM EST early this morning for ANZ635>637. && $$ |
