textproduct: NWS Wilmington

WHAT HAS CHANGED

12Z Aviation Discussion updated for the 12Z issuance.

The potential for hazardous travel conditions will continue this morning. A Special Weather Statement for black ice continues through 10 AM. A Cold Weather Advisory continues for Pender County until 9 AM for temperatures as low as 10 degrees.

Rain chances have increased inland Wednesday afternoon and along the coast Wednesday evening.

KEY MESSAGES

1) Hazardous travel conditions and cold temperatures continue this morning.

2) Rain chances have increased for Wednesday into Wednesday night, and there is still some potential cold air will arrive quickly enough for precipitation to end as freezing rain early Thursday morning.

DISCUSSION

KEY MESSAGE 1: Hazardous travel conditions and cold temperatures continue this morning.

Hazardous travel and cold temperatures remain a concern this morning. While some areas that received more snowfall may still be dealing with poor road conditions, our entire area has the potential for areas of black ice, even where significant melting has occurred. A Special Weather Statement remains in effect for black ice until temperatures rise above freezing: around 10 AM. Primary roads may look dry or less treacherous than secondary and local roads, but the higher speeds on these primary roads can be very dangerous when black ice is prevalent. Bridges, overpasses, and shady sections of roadways likely have not melted to the degree that the majority of area roadways have, so use caution while driving. With a higher traffic volume, use extra caution by slowing down, increase following distances, and remain alert for black ice.

KEY MESSAGE 2: Rain chances have increased for Wednesday into Wednesday night, and there is still some potential cold air will arrive quickly enough for precipitation to end as freezing rain early Thursday morning.

A positively tilted upper trough will drop through the Mississippi Valley on Wednesday and should move across the Carolinas Thursday. Mid level flow will become backed just enough on Wednesday to lift a stream of Gulf moisture overhead. Precipitable water values should increase to 0.9 to 1.0 inches while modest isentropic lift expands at all levels between 290K-305K. PoPs have been increased to 80-100 percent. Temperatures during the day Wednesday should generally be in the 40s, precluding any precipitation type issues at that time.

A wave of low pressure developing along a surface cold front across Georgia Wednesday afternoon will move across the eastern Carolinas Wednesday night and out to sea. Shallow cold advection will begin as the front moves offshore and temperatures should dive through the 30s, likely moving down toward the freezing mark by daybreak Thursday morning for all but the Grand Strand.

00z runs of both the GFS and NAM suggest the top of the post-frontal moist layer will extend only up to 800 mb or about 6000 feet AGL. Temperatures at this level should remain warmer than -5C meaning it's unlikely there will be ice within the clouds. This means if sufficient lift exists to generate precipitation late Wednesday night into Thursday morning, rain or freezing rain (but no snow) would occur depending on surface temperature. Usually in situations where cold air is chasing moisture like this, the amount of frozen/freezing precipitation that falls does not become significant. However given that only a trace of freezing rain constitutes a Winter Weather Advisory-worthy event we'll need to watch this one closely.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

High confidence VFR. Light winds turn southerly this afternoon ahead of the next cold front. VFR CIGs develop near the end of the TAF period. Some showers may develop by the end of the period. There may also be a brief period of LLWS late tonight.

Extended Forecast... Mainly VFR. A cold front will bring the next chance of widespread precipitation and restrictions late tonight through early Thursday. VFR thereafter.

MARINE

Through Tonight...Southerly winds increase tonight ahead of the next cold front. Gusts up to 20 or 25 knots and seas up to 3-4 feet will remain below SCA thresholds.

Wednesday through Saturday Night...Moderate southwest winds Wednesday will be accompanied by increasing rain chances as Gulf moisture moves across the area ahead of an approaching cold front. The front should make it off the NC/SC coastline Wednesday night with a shift to brisk northerly winds expected. During the period of strongest north winds it's possible we could reach Small Craft Advisory criteria (25 kt) near and north of Cape Fear on Thursday.

There will be a short lull in winds late Thursday night into Friday morning as a ridge of high pressure quickly traverses the area, however increasing westerly winds will develop Friday afternoon and especially Friday night as the next cold front arrives. Expect another shift to cold northerly winds behind the front late Friday night into Saturday.

CLIMATE

Record low temperatures were observed across the area Monday morning, including our four climate sites. Notably, Lumberton (KLBT) recorded a low temperature of -1F, which is tied for 2nd all-time coldest temperature on record. Florence (KFLO) got down to 8F, which is tied for 3rd coldest on record and is the record low for the month of February. Wilmington's (ILM) low of 14F this morning breaks previous record low for Feb 2 of 17F (set in 1980) and North Myrtle Beach (CRE) low of 19F breaks previous record low of 20F set in 1945.

ILM WATCHES/WARNINGS/ADVISORIES

NC...Cold Weather Advisory until 8 AM EST this morning for NCZ105. SC...None. MARINE...None.