textproduct: Wakefield

WHAT HAS CHANGED

Coastal Flood Advisories have been added to the bay side of the MD Eastern Shore for tonight's high tide cycle. In addition, all coastal Flood Watches have been upgraded to Coastal Flood Warnings.

Wind advisories have been added for the immediate coast as winds will likely gust in excess of 50mph Wed afternoon into Thursday night.

Shower and storms have developed along a stalled boundary across SE portions of the area, leading to locally heavy rainfall/flash flooding.

Temperatures continue to trend cooler Wednesday through Thursday. Introduced rain chances across far NE portions of the area Saturday-Sunday. Confidence in the forecast for this weekend remains below average due to uncertainties with a developing coastal low.

KEY MESSAGES

1) Heavy rain continues across southeastern portions of the area into this evening as a front lingers across the area. Cooler, CAD conditions take hold for the remainder of the forecast 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 PM EDT Tuesday...

KEY MESSAGE 1...Heavy rain continues across southeastern portions of the area into this evening as a front lingers across the area. Cooler, CAD conditions take hold for the remainder of the forecast area.

This afternoon, high pressure is situated over Ontario, Canada extending over into New England and into northern portions of the Mid Atlantic. A nearly stationary front is draped across southeastern portions of the forecast area (roughly along the VA/NC border). Very heavy rain showers (and isolated storms) have developed along and just to the north of the boundary over Hampton Roads where multiple Flash Flood Warnings are in effect. Very efficient, warm rainfall processes, this afternoon thanks to flow off the warmer Atlantic/Chesapeake Bay waters combined with maximized PWATs of ~2+" over SE Virginia. We have seen rainfall rates of 5"+ per hour at times this afternoon with the current showers. Additional Flash Flood Warnings will likely be needed across portions of Hampton Roads/SE Virginia and potentially into NE North Carolina later this afternoon and evening as the activity continues to slide south. Rainfall rates should gradually lighten up later this evening into tonight as a cooler wedge airmass continues to push into the area from the north. It's a much different story for locations outside of SE VA/NE NC where we are seeing low clouds and mist/light showers, combined with much cooler temperatures in the 60s to lower 70s due to the developing CAD wedge. Temperatures tonight will range from the mid 50s NW to around 70 SE.

Additionally, northeast winds will increase throughout this evening and into tonight 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 to 30 mph. The Atlantic coast of the Eastern Shore including Ocean City and Chincoteague will see their gusts build to 40 to 45 mph overnight. These higher gusts will persist for the coastline through Thursday night. Further inland, gusts to ~20mph are expected.

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. It is possible that far NW portions of the area (Louisa) may stay in the upper 50s. Inland ~20 mph wind gusts are forecast through the day. Winds for coastal counties will persistently be blowing around 20 to 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 and even into Friday as the tightened pressure gradient between the strong high pressure to the north and the strengthening low pressure over the ocean remains. With the CAD wedge in place, the environment will be stable leading to mainly steady stratiform rain across the area on Wednesday and Thursday. Lows will cool off a few more degrees Wednesday night with low to mid 50s inland and low 60s east.

Rain chances 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 still disagree on exactly where the low will be on Friday, with the GFS moving it off to the northeast while the ECMWF still 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, the NBM solution is mostly a blend of the two solutions, keeping low-end rain chances lingering along the coast (especially NE) through the weekend. It is possible that the forecast may change substantially over the next few days for the weekend as we get more clarity on the placement of this coastal low.

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 far northwestern and western cool spots 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 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 prevail around 20-25 kt with gusts already pushing 30kt this afternoon. The stronger NE winds likely from tonight through Thursday night. This will likely 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 now including the bay side of the MD Eastern Shore as this mornings high tide cycle has over performed. These Advisories go into effect from now through the start time of the Coastal Flood Warnings (Wed morning-evening depending on zone). A significant rise in tidal anomalies is forecasted for tomorrow. Moderate tidal flooding could begin along the upper James and tidal Rappahannock/Potomac rivers by tomorrow morning, with widespread moderate to locally major flooding forecast during tomorrows evening high tide. Moderate to locally major flooding is expected to continue through at least the Thursday evening/night high tide. With high enough confidence in the forecast and observing tides slightly higher this morning Coastal FLood Watches have been upgraded to Coastal Flood Warnings. These warnings go into effect for a large majority of the tidal area beginning tomorrow evening for most and Wednesday morning for tidal southern Potomac, Rappahannock, and upper James rivers. 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 /19Z TUESDAY THROUGH SUNDAY/

As of 200 PM EDT Tuesday...

This afternoon, a frontal boundary is slowly sagging south across the area. At RIC and off to the NW, a cool air wedge has set up with widespread low IFR CIGs. At the remaining sites, we are we are currently seeing widespread MVFR CIGs. As the front continues to sag south, widespread IFR CIGs as well as mist/light rain showers will take hold across much of the area. Our coastal sites (SBY, ORF, and ECG) likely stay MVFR through the forecast period. In addition, very heavy rain showers/storms have developed across SE portions of the area this afternoon along the front which will allow for localized periods of IFR VSBYs. NE winds become gusty, especially along the coast, later this evening and especially tomorrow with gusts of 25 to 30+ knots possible.

Outlook: An unsettled pattern is expected to persist through most of the upcoming week. At least intermittent degraded flight conditions are 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 into the weekend.

MARINE

As of 350 PM EDT Tuesday...

Key Messages:

- SCA level winds continue through tonight before changing over to Gale conditions by late tonight early tomorrow morning.

- Prolonged period of Gale force winds are likely to continue through much of the week and possibly into the weekend.

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

Afternoon weather analysis shows a 1012mb low sitting right off the OBX. The pressure gradient from this deepening low has tightened over the area allowing winds to increase out of the NE around 20- 25kt with gusts approaching 30kt+. Seas through the day have also already begun to build with buoys already reporting 5-8ft seas across the ocean and 3-4 across the bay. Small Crafts are already in effect for all waters. By late afternoon/early evening SCA will be replaced by Gale Warnings marine conditions rapidly deteriorate. Winds are expected to increase to 30-35kt with gusts approaching 40kt across the bay, ocean, sound, and lower James River. While across the tidal rivers high-end SCAs are in effect, however, a few 35kt gusts cannot be completely ruled out. By tomorrow the pressure gradient is expected to tighten as a stronger CAA surge arrives. Winds will likely remain around 30-35kt with gusts nearing 40 kt. The strongest winds are likely to impact the local waters tomorrow night into Thursday as 925 winds likely increase to 40-45kt and the stronger CAA arrives. 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 tomorrow evening-Thu timeframe. 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. By Thursday night, there is likely a brief decrease in the winds 20-25 kt on the bay/Lower James. However, over the open seas winds look to remain ~30kt with gusts approaching 35kt allowing for Gale conditions to possible prevail through Thursday night into Friday and possibly through the majority of the weekend. Will note, that there is still much disagreement with the deterministic and ensemble guidance. Nonetheless, dangerous marine conditions are likely to prevail.

Dangerous surfing conditions have begun this afternoon 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 are in effect for all beaches starting this afternoon for the northern beaches and tonight for the southern beaches and are expected to continue through early Thursday evening for now.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...Coastal Flood Advisory from 8 PM this evening to 5 AM EDT Wednesday for MDZ021>023. Coastal Flood Warning from 6 PM Wednesday to 4 AM EDT Friday for MDZ021>023. Coastal Flood Advisory until 4 PM EDT Wednesday for MDZ024-025. Coastal Flood Warning from 4 PM Wednesday to 4 AM EDT Friday for MDZ024-025. High Surf Advisory from 2 AM Wednesday to 6 PM EDT Thursday for MDZ025. Wind Advisory from 2 PM Wednesday to 8 PM EDT Thursday for MDZ025. NC...Wind Advisory from 2 PM Wednesday to 8 PM EDT Thursday for NCZ017-102. High Surf Advisory from 7 AM Wednesday to 6 PM EDT Thursday for NCZ102. Coastal Flood Warning from 11 AM Wednesday to 4 AM EDT Friday for NCZ102. VA...Coastal Flood Advisory until 4 PM EDT Wednesday for VAZ083-084- 099-100-518-520-523. Coastal Flood Warning from 4 PM Wednesday to 4 AM EDT Friday for VAZ083-084-099-100-518-520-523. High Surf Advisory from 2 AM Wednesday to 6 PM EDT Thursday for VAZ099-100. Wind Advisory from 2 PM Wednesday to 8 PM EDT Thursday for VAZ098>100. High Surf Advisory from 7 AM Wednesday to 6 PM EDT Thursday for VAZ098. Coastal Flood Advisory until 5 AM EDT Wednesday for VAZ075>078- 085-086-521-522. Coastal Flood Warning from 5 AM Wednesday to 8 AM EDT Friday for VAZ075>078-085-086-521-522. Coastal Flood Warning from 6 AM Wednesday to 4 AM EDT Friday for VAZ081-082-089-090-524-528. Coastal Flood Advisory until 6 AM EDT Wednesday for VAZ089-090- 524-528. Coastal Flood Advisory until 2 PM EDT Wednesday for VAZ097-098- 525-529>531. Coastal Flood Warning from 2 PM Wednesday to 4 AM EDT Friday for VAZ097-098-525-529>531. MARINE...Small Craft Advisory until 4 AM EDT Wednesday for ANZ630>632- 634. 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 until 7 AM EDT Wednesday for ANZ633-639- 658. Gale Warning from 7 AM Wednesday to 10 PM EDT Thursday for ANZ633-639. Small Craft Advisory until 7 AM EDT Friday for ANZ635>637. Small Craft Advisory until 6 PM EDT this evening for ANZ650- 652-654. Gale Warning until 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 until 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.