textproduct: Newport/Morehead City

WHAT HAS CHANGED

Winter Storm Watch has been trimmed in timing a bit to end early Sunday afternoon, as a warmer and drier airmass will lift into Eastern NC Sunday afternoon ending the icing threat.

Gale Watch has been converted to a Gale Warning for all of the coastal waters, with Small Craft Advisories now in effect for Pamlico/Roanoke/Croatan/Albemarle sounds and the inland rivers.

KEY MESSAGES

1) An Arctic front will push through the area Friday night with a low pressure system passing through ENC this weekend, bringing a wintry mix of some snow, but mostly sleet and freezing rain to ENC, especially inland areas. Winter Storm Watch remains in effect for the western counties of the Coastal Plain of ENC.

2) Cold airmass builds in behind the system through much of next week with below normal temperatures with highs in the 35-45 degree range and lows 15-25.

DISCUSSION

KEY MESSAGE 1... An arctic cold front will push through the area late Friday, with scattered areas of light rain ahead of it during the day. Temps will be in the 50s and precip will be all liquid. Arctic high pressure builds into the area from the north Friday night behind the front and sets the stage for overrunning wintry mix on Sat as isentropic ascent increases and wet bulbing keeps surface temps only in the 30 degree range or so throughout the day for much of the region. Cold apparent temperatures will be in place Friday night into Saturday morning with values below 15 degrees possible for northern and western counties. Mix of snow and sleet will likely break out across ENC late Saturday morning but increasing into the afternoon and evening hours as isentropic ascent increases. Limited accums expected during the day as QPF amounts will be quite light, amounting to only several hundredths of an inch. However, with cold air and ground temps, some slick spots will likely begin to develop on some of the elevated surfaces away from the coast where temps hover around in the upper 20s to lower 30s much of the day.

By Saturday night, low pressure will develop along stalled front, coastal trough offshore and begin to more northeastward and penetrate into Eastern NC through the overnight. The big change with this forecast is Sat night into Sun. This brings substantial warming aloft, with 850mb temps fcst to reach between 5-10C by daybreak Sunday, while stubborn CAD remains at the sfc west of Hwy 17. Consensus from other 22/12Z model guidance appears to be converging on the consistent Euro solution from the last several cycles, which brings sfc warming above freezing from E to W across ENC through the overnight, limiting duration of icing for areas along and east of Hwy 17. West of Hwy 17, the CAD holds strong through Sunday morning, leading to more prolonged QPF at below freezing temps, and the watch area looks very good and no changes to areal extent. At this time fzra amounts look to be in the .20"-.30" range, with locally higher amounts up to around 0.50" for far western communities. Have adjusted end time to 2pm for two reasons. Number one, CAD will erode further inland and temps rise above freezing in the afternoon, and the warm sector dry slot will overspread ENC as the low moves through the area.

Regarding winds with arctic front Fri night and Sat morning, it appears the surge will be brief enough and a bit more marginal for wind adv headlines on the OBX attm. Water level rises may rise a bit above normal for southern areas of Pamlico Sound, but the drought that has been in place and the below average water levels already in place should prevent any impacts.

KEY MESSAGE 2...

Arctic high pressure will build in behind the departing system through much of next week. Temperatures will be quite a bit below normal, with highs in the 35-45 degree range, and lows in the 15-25 degree range. Wind chill values will possibly dip down through the teens each night and morning beginning Monday night through much of next week.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

VFR conditions are expected through most of the TAF period with deteriorating CIGs tomorrow. Tonight, skies will be OVC with CIGs around 6-7 kft and scattered light showers. Light westerly winds will veer to the NNE by sunrise. Tomorrow, scattered light showers will continue as CIGs lower through the remainder of the period. OAJ will be flirting with CIGs near MVFR by the afternoon and is expected to drop below 3 kft around or just after 00z. EWN and ISO will be hovering just above MVFR CIGs by tomorrow evening, but they've been kept VFR with this TAF cycle. Light NW winds will back to the NNW through the day.

Outlook: An extended period of sub-VFR conditions is likely this weekend as a significant winter storm impacts the area. All winter precip types are possible through the weekend, although it looks like a mix of rain/freezing rain will be the dominant P-Types. KISO and KPGV are expected to receive the greatest impacts due to ice accumulation but ice will be possible at all terminals.

MARINE

Latest obs show SW winds 5-15 kt with some higher gusts on the warmer gulf waters Light to moderate winds cont through tonight with seas mainly 2-4 ft.

Friday through Monday: Gales have been upgraded to warnings for the coastal waters late Friday night into Saturday, with small craft advisories for the sounds and rivers. An arctic front will push through Friday night into Saturday and the resultant strong northerly winds will quickly build seas to 6+ ft. Winds become E-SE Sat night then swrly on Sunday as low pressure tracks just inland from the coast. SCA conditions likely for the warmer and well mixed gulf stream waters, with sub 20 kt winds elsewhere.

MHX WATCHES/WARNINGS/ADVISORIES

NC...Winter Storm Watch from Saturday afternoon through Sunday afternoon for NCZ029-044-079-090-091. MARINE...Small Craft Advisory from 1 AM Saturday to midnight EST Saturday night for AMZ131-135>137-230-231. Gale Warning from 1 AM to 8 AM EST Saturday for AMZ150. Gale Warning from 1 AM to noon EST Saturday for AMZ152-154. Gale Warning from 3 AM to noon EST Saturday for AMZ156-158.