textproduct: Newport/Morehead City

WHAT HAS CHANGED

Small Craft Advisory has been cancelled for central waters. PoPs decreased for today, and increased for Thursday. Marine wind gusts increased for Saturday.

KEY MESSAGES

1.) Line of scattered showers with maybe a thunderstorm or two possible tonight. Severe thunderstorm chances decreased.

2) MCS moving through the Carolinas Thursday bringing chances of rain.

3.) Rain arrives this weekend as a low pressure system develops off of the southeast coast on Saturday and drags a frontal system through the area Saturday night.

Marine: Small Craft Advisory cancelled. Heightened winds and seas possible this weekend.

DISCUSSION

KEY MESSAGE 1... A series of weak shortwaves rotating around an upper low centered north of the Great Lakes will push across the area over the next couple of days. An initial shortwave and attendant low pressure system will move out of the mid-Mississippi Valley and push northward through the Ohio Valley today. Mid level dry layer paired with no instability and a lack of forcing have resulted in an underwhelming amount of precip this afternoon. Generally dry conditions expected to continue into the evening, before a cold front moves through tonight. Ahead of the cold front, scattered showers and maybe a thunderstorm are possible. However, meager instability given nocturnal stability precludes any notable severe threat.

KEY MESSAGE 2...Another shortwave bringing an MCS with it will trek across the Carolinas Thursday. There is some uncertainty of how north the precip shield extends, with PoPs decreasing the further north you go. NBM has not resolved this trend in guidance yet, so went well above NBM in this forecast cycle. Thunder chances remain low enough to keep out of the forecast Thursday over land with the MCS, with some reinvigoration possible once the MCS encounters warm gulf stream waters.

KEY MESSAGE 3...An increasing chance for much needed rainfall will be on Saturday as a low pressure develops off of the southeast coast and works its way over eastern NC. As this is happening an upper level low centered over Ontario and Quebec will work to deepen an upper level trough that will begin to push a supporting wave out of Texas which will eventually elongate into the frontal system that will accompany the coastal low. The merged systems will push through Saturday night into Sunday and move offshore but not before some significant rainfall areas along the coast having a 50-75% chance of at least an inch of rainfall, decreasing to 30-50% chance inland.

As far as convection is concerned, currently most of the instability remains offshore with northerly flow keeping profiles more stable over land. This should keep rainfall rates low enough to preclude any flash flooding threat, especially when paired with the drought conditions in place. Still a lot of uncertainty in the models regarding how strong the low will get and will have to monitor as the system gets closer.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/

Some patches of lower ceilings (2500-3000 ft) will exist for the next few hours this afternoon, while other areas across ENC see ceilings in the range of 3500-4000 ft. VFR conditions are expected this evening and tonight, however a broken line of showers and thunderstorms will move from NW to SE across the forecast area, and could lead to some temporary reductions to MVFR levels. Thereafter, VFR conditions will continue the rest of the tonight and through the day tomorrow.

Outlook: Back to mainly VFR Thu into Fri, then conditions deteriorate Fri night through Sat as widespread rain with lowered cigs afflict ENC. Winds generally in the 5-15 kt range through the rest of the week. The low pres area clears out by Sunday with return to VFR.

MARINE

Currently seeing light winds less than 15 kt across the waters, mainly out of the southeast, with seas around 3-5 ft. Winds will gradually increase to around 10-20 kt this evening as low pressure passes north of the area, then will become NW to N late tonight behind a cold front. Could see a few gusts to 20-25 kt tonight with best chances over the Gulf Stream waters, but most areas should remain below SCA criteria. Wave guidance is overperforming, with models indicating 6-7 ft over diamond shoals, when current obs are 4-5 ft. For this reason, elected to cancel the SCA that was in place until Friday morning. Cold front moving through tonight may bring some thunderstorms capable of gusty winds along marine zones. Thursday late morning through the afternoon a MCS moves through our waters, with thunderstorm chances returning for warm gulf stream waters where instability is the highest.

Outlook: Another low pressure system may pass across or just south of the waters late in the week which could bring another chance for small craft advisory criteria to be met Saturday into Sunday.

MHX WATCHES/WARNINGS/ADVISORIES

NC...Beach Hazards Statement until 8 PM EDT this evening for NCZ203- 205. MARINE...None.