textproduct: Wakefield

WHAT HAS CHANGED

Gale Warnings, High Surf Advisories, and ramp-up Coastal Flood Advisories have been issued beginning later today.

Potentially drying out late week into the weekend, though model differences remain.

KEY MESSAGES

1) Rain is expected to become more widespread today as a front lingers across the area.

2) Strong onshore flow, cooler temperatures, and rainy conditions will continue on Wednesday. Rain chances gradually shift east Thursday, potentially making for a dry end to the week. Gusty winds will persist.

3) Widespread moderate to locally major tidal flooding (inundation of 2-3 feet AGL in vulnerable areas) is likely by the Wednesday afternoon/evening high tide due to strong northeast winds. Tidal flooding is expected to continue for several tide cycles given the persistent northeast winds.

DISCUSSION

As of 315 AM EDT Tuesday...

KEY MESSAGE 1...Rain is expected to become more widespread today as a front lingers across the area.

Early morning surface analysis shows a broad area of high pressure over Ontario, Canada extending outwards into New England and portions of the Mid-Atlantic. The cold front that passed through our area today is currently draped across central and southern NC. Low cloud cover persists across the CWA with showers moving along the northern boundary across northern VA and portions of the MD Eastern Shore. Rain is expected to become more widespread later this morning as the front lifts back north. Exact coverage and timing of the rain has a slightly lower confidence, but today will have the best rain chances of the last few days. Some isolated thunderstorms can't be totally ruled out for the southern half of the area, which could lead to heavy downpours and localized flash flooding. A couple of efficient storms along the NC/VA border into NE NC last evening produced 2-3" of rain in a short period, which even caused over a foot of rise on the Cashie River in Windsor. Expect the same efficient rainfall makers to be possible again today. WPC has a Slight Risk of Excessive Rainfall for the southeast half of the CWA, excluding the SE VA and NE NC coast.

Additionally, northeast winds will increase later this morning as the Canadian high pressure shifts east and low pressure forms off the NC/SC coast. Locations along the coast, including the entire Eastern Shore, Norfolk, Hampton Roads, and into Currituck County will see wind gusts upwards of 25-30mph by this afternoon. The Atlantic coast of the Eastern Shore including Ocean City and Chincoteague will see their gusts build to 40-45mph overnight. These higher gusts will persist for the coastline through Thursday night. Further inland, gusts to ~20mph are expected starting this afternoon. High temperatures will be noticeably cooler for most of the area today as the cooler airmass works its way in from the north. High temperatures will range from the upper 60s across the north to the lower 80s along the south. Lows tonight will dip into the upper 50s for our western counties, with upper 60s for the southeast.

KEY MESSAGE 2...Strong onshore flow, cooler temperatures, and rainy conditions will continue on Wednesday. Rain chances gradually shift east Thursday, potentially making for a dry end to the week. Gusty winds will persist.

Cold air damming will overtake the area on Wednesday as high pressure remains parked to our north. This will make for our coolest day of the week as high temperatures top out in the low to mid 60s for the western and northern inland areas, with low 70s for the SE half of the CWA. Inland gusts to 20mph are forecast through the day. Winds for coastal counties will persistently be blowing around 20-25mph with gusts to 35+mph. The strongest winds will continue to be along the Atlantic coast with gusts to 40-45mph expanding down the span of our coastline through the day on Wednesday. These winds are forecast to stick around through Thursday night as the tightened pressure gradient between the strong high pressure to the north and the strengthening low pressure over the ocean remains. This persistent onshore flow will create really rough beach conditions, as high surf/wave heights and beach erosion are likely. Wednesday will also be when moderate to locally major coastal flooding starts, so if you live in a coastal zone, please read our tidal flooding section below and stay tuned to the latest forecasts. With the CAD wedge in place, the environment will be stable leading to steady stratiform rain across the area. While it won't have the higher intensity rates of a thunderstorm (since we will be too capped for those), the persistent rainfall could still create some flooding concerns. Lows will cool off a few more degrees Wednesday night with low to mid 50s inland and low 60s east.

Rain chances then look to become more confined to eastern portions of the area Thursday into the first part of Friday as a secondary surface low forms along our coast and causes the main low to deepen, as well as finally have the potential to gain some forward momentum. Models disagree on exactly where the low will be on Friday, with the GFS moving it off to the northeast while the ECMWF keeps it closer to our shore. One solution will allow for winds to subside later Friday and drier air to move in for the weekend, while the other keeps the elevated impactful conditions lingering a bit longer. For now, went with rain chances ending Friday making way for a mostly dry weekend. Winds will likely shift to be more N/NW overnight Thursday into Friday. This will allow speeds to subside a bit, but gusts to 25-30mph may still be possible into the weekend.

Highs on Thursday will still be well below normal as the effects of the CAD remain, with lower 60s forecast west of I-95 and upper 60s to lower 70s to the east. Thursday night will be rather chilly with some far northwestern and western cool spots potentially dipping into the upper 40s. If the low is able to shift to the northeast, our winds will turn northerly Friday, as mentioned above, giving another chance for more of the area to see lows in the lower 50s (likely everyone except the coast). Highs will begin to moderate back into the lower 70s Friday into the weekend.

KEY MESSAGE 3...Widespread moderate to locally major tidal flooding (inundation of 2-3 feet AGL in vulnerable areas) is likely by the Wednesday afternoon/evening high tide due to strong northeast winds. Tidal flooding is expected to continue for several tide cycles given the persistent northeast winds.

Northeast winds increase to 20-25 kt today with strong NE winds likely from tonight through Thursday night. This will will cause water levels to rise across much of the area (especially along the bay, tidal rivers, and Atlantic coast). Widespread minor tidal flooding is expected by this evening/tonight's high tide. Ramp up Coastal Flood Advisories have been issued for much of the area (except the bay side of the MD Eastern Shore) from later today through the start time of the Coastal Flood Watch (Wed morning- evening depending on zone). A significant rise in tidal anomalies is forecast on Wednesday. Moderate tidal flooding could begin along the upper James and tidal Rappahannock/Potomac rivers by Wed AM, with widespread moderate to locally major flooding forecast during the Wednesday evening high tide. Moderate to locally major flooding is expected to continue through at least the Thursday evening/night high tide. Coastal FLood Watches remain in effect for a large majority of the tidal area beginning Wednesday evening for most and Wednesday morning for tidal southern Potomac, Rappahannock, and upper James rivers. While it is a bit too early for Coastal Flood Warnings, expect the watches to be upgraded to warnings with later forecast packages. While water levels should gradually fall Friday- Saturday as winds diminish a bit and become NNW, minor to moderate tidal flooding seems likely through at least Friday evening and possibly longer.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

As of 630 AM EDT Tuesday...

MVFR conditions persist across most of the area this morning. CIGs are generally BKN-OVC015, though there are some pockets of IFR, particularly at SBY. Guidance indicates that IFR will likely develop at RIC after ~12Z as well. NE winds are 6-8kt currently, but will become 12-17kt with gusts up to ~25kt for eastern terminals after 14Z. RIC could see some gusts to 18-20kt this afternoon as well. These gusty winds and mix of IFR CIGs to the north and MVFR to the south will continue through the TAF period. Confidence in exact SHRA coverage through the day today is low, but guidance has high enough chances to include as prevailing groups for now. Did push back RA timing for southern terminals until this afternoon. Slightly higher confidence exists at RIC where the better RA chances will be today. Regardless, VIS restrictions from the RA/BR are expected.

Outlook: An unsettled pattern is expected to persist through most of the upcoming week. Wed should continue to see widespread flight restrictions, with at least intermittent degraded flight conditions likely through Thursday. Coastal terminals will also have elevated NE winds for an extended period, with winds remaining elevated and shifting to the N-NW Fri-Sat.

MARINE

As of 315 AM EDT Tuesday...

Key Messages:

- SCA level winds are forecast today with east to northeast winds increasing to 20 to 25 kt by the afternoon. Ramp up SCAs have been issued for all marine zones that are under Gale Warnings.

- Confidence in a period of gales with NE winds remains very high from tonight-Thursday/Thursday night. Gale Watches have been upgraded to Gale Warnings for the ocean, bay, Lower James River, and Currituck Sound. High-end SCAs have been issued for the upper rivers.

- Seas build to 10-14+ feet, likely leading to dangerous marine conditions.

Early morning wx analysis shows that the actual cold front is to the south of the waters, with E-NE winds of 10-20 kt (highest north) and 3-6 ft seas. While the front is to our south, the strongest CAA will take some time to reach the marine area. Conditions start to deteriorate today with E-NE winds increasing to 20-25 kt by late in the day. While guidance has come down by a knot or two with respect to wind, there really is not a whole lot of change in forecast thinking given the setup (impressive sfc high to our north/CAA over warm waters). While a few gale force gusts are possible north of Parramore Island by early evening, the first surge of stronger CAA arrives tonight as the 1035-1040mb builds across eastern Canada and low pressure begins to gradually deepen a couple hundred miles offshore of the VA/NC coast.

Rapidly deteriorating marine conditions are expected across the bay and ocean overnight, with winds increasing to ~30 kt by Wed AM with gusts to 40 kt. Gale Watches have been upgraded to Gale Warnings for the bay, ocean, and lower James River. High-end SCAs have been issued for the upper rivers starting this evening-tonight (where a few gusts to 35 kt are possible but confidence was not high enough to go w/ Gale Warnings). The pressure gradient tightens further on Wed/Wed night as a stronger CAA surge arrives. Winds are forecast to remain around 30 kt with gusts 40 kt on Wed, with the strongest winds still expected Wednesday night through Thursday as the strongest CAA arrives. 925mb winds are progged to increase to 40-45 kt during this time. With the unstable marine boundary layer and water temps in the mid to upper 70s, wind gusts at that level should easily be able to mix down to the sfc. Therefore, confidence is fairly high that we will see a period of sustained gale force winds with gusts to 45 kt across the ocean and lower bay during the Wed evening-Thu timeframe. Will continue to mention gusts as high as 45 kt in the MWW/CWF. which would lead to a period of sustained gale force winds with gusts to 45 kt. Gale Warnings run through Thursday evening for the upper bay, part of Thu night for the lower bay/lower James, Friday morning for the ocean, and Friday afternoon for the offshore (20-60nm) coastal waters. There is decent consensus in the global models that winds become more northerly and diminish to 20-25 kt on the bay/Lower James Thursday night and to just below gale criteria 0-20nm offshore Friday morning. While low pressure is progged to rapidly deepen well offshore Friday-Saturday, model/ensemble consensus shows it far enough away from the coast that gale gusts would be confined to the 20-60nm offshore zones after Friday morning. Winds gradually turn to the NNW by Fri night/Sat AM. Local wind probs for 34+ kt gusts remain near 100% through Thu, but drop to below 10% on the bay by early Fri AM, and fall to 10-20% out to 20nm by late Friday morning. Therefore, did not expand Gale Warnings too far out in time (except for the 20-60nm zone). Nevertheless, will still have to monitor the rapidly deepening offshore low Fri/Sat, and forecast changes are possible if it looks like it will deepen closer to the coast. Given the prolonged strong NE winds, seas are forecast to build to 10-14+ ft. This will likely lead to dangerous marine conditions from late Tuesday night through Thursday night.

Dangerous surfing conditions are likely by late today and will continue through Thu with the prolonged onshore flow, and remain high into the weekend due to elevated seas even as the winds become NNW. Localized beach/dune erosion is possible from mid to late week as well. High Surf Advisories have been issued for all beaches starting late today and continuing through early Thursday evening for now.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...Coastal Flood Watch from Wednesday evening through late Thursday night for MDZ021>023. Coastal Flood Advisory from 4 PM this afternoon to 4 PM EDT Wednesday for MDZ024-025. Coastal Flood Watch from Wednesday afternoon through late Thursday night for MDZ024-025. High Surf Advisory from 2 AM Wednesday to 6 PM EDT Thursday for MDZ025. NC...High Surf Advisory from 7 AM Wednesday to 6 PM EDT Thursday for NCZ102. Coastal Flood Watch from Wednesday morning through late Thursday night for NCZ102. VA...Coastal Flood Advisory from 4 PM this afternoon to 4 PM EDT Wednesday for VAZ083-084-099-100-518-520-523. Coastal Flood Watch from Wednesday afternoon through late Thursday night for VAZ083-084-099-100-518-520-523. High Surf Advisory from 2 AM Wednesday to 6 PM EDT Thursday for VAZ099-100. High Surf Advisory from 7 AM Wednesday to 6 PM EDT Thursday for VAZ098. Coastal Flood Advisory from 10 AM this morning to 5 AM EDT Wednesday for VAZ075>078-085-086-521-522. Coastal Flood Watch from late tonight through Friday morning for VAZ075>078-085-086-521-522. Coastal Flood Watch from Wednesday morning through late Thursday night for VAZ081-082-089-090-524-528. Coastal Flood Advisory from 6 PM this evening to 6 AM EDT Wednesday for VAZ089-090-524-528. Coastal Flood Advisory from 4 PM this afternoon to 2 PM EDT Wednesday for VAZ097-098-525-529>531. Coastal Flood Watch from Wednesday afternoon through late Thursday night for VAZ097-098-525-529>531. MARINE...Small Craft Advisory from 10 AM this morning to 4 AM EDT Wednesday for ANZ630>632. Gale Warning from 4 AM Wednesday to 4 PM EDT Thursday for ANZ630-631. Gale Warning from 4 AM Wednesday to 1 AM EDT Friday for ANZ632- 634. Small Craft Advisory from 1 PM this afternoon to 7 AM EDT Wednesday for ANZ633-658. Gale Warning from 7 AM Wednesday to 10 PM EDT Thursday for ANZ633-639. Small Craft Advisory until 4 AM EDT Wednesday for ANZ634. Small Craft Advisory from 1 PM this afternoon to 7 AM EDT Friday for ANZ635>637. Small Craft Advisory from 10 AM this morning to 7 AM EDT Wednesday for ANZ639. Small Craft Advisory until 6 PM EDT this evening for ANZ650- 652-654. Gale Warning from 6 PM this evening to 7 AM EDT Friday for ANZ650-652-654. Small Craft Advisory until 1 AM EDT Wednesday for ANZ656. Gale Warning from 1 AM Wednesday to 7 AM EDT Friday for ANZ656. Gale Warning from 7 AM Wednesday to 7 AM EDT Friday for ANZ658. Gale Warning from 6 PM this evening to 6 PM EDT Friday for ANZ680-682-684. Gale Warning from 1 AM Wednesday to 6 PM EDT Friday for ANZ686. Gale Warning from 7 AM Wednesday to 6 PM EDT Friday for ANZ688.