textproduct: Raleigh

WHAT HAS CHANGED

As of 119 AM Monday...

* Marginal fire concerns this afternoon over the southern Piedmont and western Sandhills.

KEY MESSAGES

As of 119 AM Monday...

1) Another brisk day to start the work week. Temperatures start the week below normal but rise slightly above average by midweek. Next shot of rain comes late Wed night to early Thu.

2) Chance for showers with a cold front moving across the region Thursday night/Friday.

DISCUSSION

As of 119 AM Monday...

KEY MESSAGE 1... Another brisk day to start the work week amid marginal fire concerns. Temperatures start the week below normal but rise slightly above average by midweek. Next shot of rain comes late Wed night to early Thu.

Another brisk day will start our work week. The departing and rapidly deepened surface low off the New England coast will continue to exert its influence across the region through at least early evening. A tight pressure gradient will remain in place with the low offshore and cold high pressure in the central US. Gusts from the NW today will range from 25-35 mph. A few infrequent gusts to 40 mph are possible, but this will not be the norm as it appears deep mixing in the boundary layer may partially weaken the winds with time owing to turbulent mixing.

With the combination of these gusty winds and relative humidity levels dipping into the 25-35 percent range this afternoon, there is a marginal risk of fire spread. The limiting factors today will be colder highs in the 40s and recent 24-hr rainfall. Based on MRMS derived and observed precipitation, most of central NC received a quarter to half inch or more of rain, which should alleviate most fire concerns today. The one exception is over the southern Piedmont and far southern Sandhills to southern Coastal Plain, where rain amounts were generally a tenth of an inch or less. Fire danger appears higher here and across western NC and southeastern NC, where little to no rain occurred. We will reach out to NCFS this morning regarding any potential fire statement.

Temperatures will start the week below normal in the 40s, some 10-15 degrees below normal. Lows will follow a similar trend, with the coldest overnight lows tonight in the mid to upper 20s. Winds should weaken tonight, but may stay gusty at 15-20 mph prior to midnight. Temperatures should moderate to a few degrees above normal with values close to 60 as return flow sets in. Our next chance of precipitation comes late Wed night and early Thu as a warm front tied to a system over the Southern Plains lifts into the Carolinas. Rain amounts appear light until later Thu/Fri. Regardless, it could also be gusty from the SW Wed in the 20-30 mph range.

KEY MESSAGE 2... Chance for showers with a cold front moving across the region Thursday night/Friday.

Aloft, a s/w will track ewd across the Plains and MS Valley within the broad longwave trough on Thu, amplifying the longwave trough as it moves across the Appalachians and East Coast Thu night and Fri. A trailing s/w will move across the Deep South/Southeast US Fri/Sat, but its progression thereafter remains uncertain. At the surface, a low pressure system will develop over the srn Plains early Thu, however the medium-range model solutions varying wrt how the system progresses as it moves generally ewd Thu/Thu night. Generally expect the associated cold front to move ewd into and across the region Thu night/Fri, possibly stalling south and east of the area Fri night as high pressure tracks ewd across the cntl Appalachians and mid- Atlantic. This high should continue newd over the Atlantic on Sat, while there is some uncertainty wrt a low developing along the front over the Southeast US and its development thereafter. For now, the best chances for showers will be with the fropa between late Thu evening/night and Fri aft/eve. Additionally, the 18Z GFS has a strengthening LLJ over the area ahead of the front, with 40-50 kts at 925 mb and some 50-65+ kts at 850 mb. While there is a negligible amount of CAPE off the GFS forecast soundings, effective shear maxes out in the 20-30 kt range. While deep convection is not currently anticipated, if it were to occur then some strong wind gusts would be possible. The 925 mb winds may result in some LLWS potential. Otherwise, temperatures should generally remain near to above normal through the extended forecast period.

AVIATION /11Z MONDAY THROUGH FRIDAY/

As of 615 AM Monday...

Gusty winds will restrengthen after sunrise in addition to the development of a SCT-OVC 5-8k ft cloud layer through the afternoon/evening. After sunset, gustiness will gradually subside with clearing of the cloud deck to SKC by 12z Tues.

Outlook: VFR conditions are expected through Wed night, although the passage of a clipper wave to our north may bring a period of LLWS Tues night as a LLJ strengthens to 40-50 kts. Light rain, sub-VFR conditions, and LLWS will be possible on Thurs as a warm front lifts into/through central NC. Additional showers are likely along and ahead of a cold front Thurs night.

RAH WATCHES/WARNINGS/ADVISORIES

None.