textproduct: Raleigh

WHAT HAS CHANGED

As of 312 AM Thursday...

* The Winter Weather Advisory continues. Areas of light snow NW, areas of light snow/freezing drizzle expected elsewhere into the early morning, then models have trended cloudy and cold all day.

* Increasing confidence for strong cold NW winds on Saturday.

KEY MESSAGES

As of 315 AM Thursday...

Winter Weather Advisory is in effect through 10 AM today.

1) Areas of light snow and some freezing drizzle are expected to continue through around sunrise in the west and north. A change to light freezing drizzle and light freezing rain expected far SE before ending mid-morning. All accumulations will be light, but hazardous for travel as temperatures fall into the 20s. Cloudy and cold today with highs only in the 30s.

2) Strong winds should be expected on Saturday behind a cold frontal passage Friday night as another cold wave arrives.

3) Arctic high pressure will build in over the weekend, with temperatures 10-20 degrees below normal Saturday and Sunday.

DISCUSSION

As of 315 AM Thursday..

KEY MESSAGE 1... Areas of light snow and some freezing drizzle are expected to continue through around sunrise in the west and north. A change to light freezing drizzle and light freezing rain expected far SE before ending mid-morning. All accumulations will be light, but hazardous as temperatures fall into the 20s.

Most of the snow was located along and NW of a line from Lexington to Burlington to near RDU. Radar returns are light and rather patchy as expected except in the Foothills and NW Piedmont where steady light snow was falling. Visibilities have been in the 2-5 mile range, with an occasional 1 to 1 1/2 mile reported at Greensboro and Hickory. RDU reported a mix of light snow and freezing rain at 250 AM. As the colder and drier near surface air advects in from the north, concerns continue for hazardous travel developing quickly as readings fall into the 20s between 400 AM and 700 AM for many areas. Light rain was becoming light freezing rain in the SE as the cold air surges in. At 300 AM, the surface freezing line extended north of a line from Albemarle to Erwin to Goldsboro, moving south.

As expected, the precipitation will remain light, with additional QPF of only 0.01 to 0.10, higher south and east of Raleigh. A light dusting to 0.5 inch of snow is expected over portions of the Piedmont, with a light glaze of freezing rain in an arch from Wadesboro and Laurinburg to Goldsboro. It only takes a very light amount of ice to create hazardous travel - with bridges and overpasses the most hazardous as they will freeze first.

Most guidance suggests the areas of light precipitation will taper off by 12z-15z from NW to E, with a chilly low overcast likely to persist through the morning. Ceilings will gradually lift and clear out through the afternoon. Temperatures will be very slow to rise if at all through late morning, then highs in the mid 30s are expected this afternoon.

Lows tonight will dip into the lower to mid 20s, except 15 to 20 in the north-central Piedmont with partly cloudy skies becoming mostly clear.

Friday will be bright and sunny early, but with increasing cloudiness in the PM. the chill will linger as highs reach 40-45.

AVIATION /06Z THURSDAY THROUGH MONDAY/

As of 110 AM Thursday...

MVFR to IFR cigs and occasional vsbys will continue through 12z at all sites. Periods of light wintry precipitation will continue with predominate light snow NW and light freezing drizzle/sleet RDU and RWI, and light rain at FAY. There is still a chance of some light wintry precipitation between 12z and 15z, mainly SE of the GSO/INT areas.

A gradual improvement to MVFR then VFR will occur late morning into the afternoon, with lingering stratus becoming stratocumulus this afternoon as cigs rise to 4-5k feet by 18z-21z.

Looking beyond 21z today, any lingering sub-VFR conditions (most likely at FAY) after 00z should improve to VFR by mid evening Thu. VFR conditions should then persist through Mon, although a quick- moving system may bring very brief sub-VFR cigs and a light snow or rain shower mainly NE (RDU/RWI) Fri night. Additionally, brisk and gusty NW winds are likely Sat, which may induce mechanical turbulence.

RAH WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory through 10 AM EST Thursday for NCZ007>011-021>028-038>043-073>078-083>086-088-089.