textproduct: Raleigh

WHAT HAS CHANGED

* Person and Granville counties have been upgraded to a Freeze Warning.

KEY MESSAGES

As of 236 PM Monday...

1) A cold front tonight will bring sub-freezing lows of 29F to Granville and Person counties (Freeze Warning) and patchy frost to the northern Piedmont and Coastal Plain (Frost Advisory).

2) Temperatures will be above normal through the extended forecast period. A cold front could possibly bring some rain this weekend.

DISCUSSION

As of 236 PM Monday...

KEY MESSAGE 1... A cold front tonight will bring sub-freezing lows of 29F to Granville and Person counties (Freeze Warning) and patchy frost to the northern Piedmont and Coastal Plain (Frost Advisory).

Below-average temperatures will persist through Tuesday as a secondary cold front crosses the region this evening. This front is moving slightly slower than previously anticipated, which will delay the arrival of the coldest air and somewhat limit the extent of sub- freezing temperatures. However, as the front exits overnight, high pressure will settle over the Mid-Atlantic. This will result in clear skies and calm windsideal conditions for radiational cooling where temperature could quickly drop. Thus, a Freeze Warning is now in effect for Granville and Person counties from 2 to 8 am Tuesday, with lows expected to reach 29F. A Frost Advisory remains in effect for the northern Piedmont, northern Coastal Plain, and portions of the northern Sandhills. Residents in these areas should expect temperatures between 33F and 36F, creating the prime environment for patchy frost especially in rural areas that can damage uncovered outdoor plants.

KEY MESSAGE 2...Temperatures will be above normal through the extended forecast period. A cold front could possibly bring some rain this weekend.

With a shift to southerly flow on Wednesday, temperatures will rise above normal, with highs in the 80s through at least Saturday, and bring an end to any overnight temperatures around freezing. While some models suggest that areas along the VA/NC border could receive a brief sprinkle Wednesday afternoon/evening, have removed the chance of rain from the forecast considering how dry the sub-cloud layer in the atmosphere will be. A more substantial chance of rain will arrive this weekend with a cold front, but considering how yesterday's cold front underperformed with rainfall totals, will not get too optimistic about rain chances this weekend until that time period is closer. Whether or not much rain occurs with the front, a shift in surface winds back to the north should drop highs back into the 70s for most locations on Monday.

AVIATION /00Z TUESDAY THROUGH SATURDAY/

As of 555 PM Monday...

Surface cold front and associated 7-9kft cu deck continues to slide southward through NC this afternoon. What little cloud cover remains at 00Z will quickly move south of the area and/or dissipate, yielding clear skies through at least Tuesday afternoon. Breeziness will also subside around 00Z, with winds gradually veering out of northeast tonight and eventually out of the southwest Tuesday afternoon between 5-8kts.

Outlook: VFR weather expected through the end of the week with the potential for non-VFR weather returning this weekend.

RAH WATCHES/WARNINGS/ADVISORIES

Freeze Warning from 2 AM to 8 AM EDT Tuesday for NCZ007-008. Frost Advisory from 2 AM to 8 AM EDT Tuesday for NCZ009>011- 021>028-038>043-076.