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000
FXUS62 KRAH 241025
AFDRAH

AREA FORECAST DISCUSSION
National Weather Service Raleigh NC
625 AM EDT Fri May 24 2019

.SYNOPSIS...
A strong ridge of high pressure aloft over the Deep South and
Southeast will persist through the weekend into early next week.
This will promote a period of above normal temperatures and limited
precipitation chances.
&&

.NEAR TERM /THROUGH TONIGHT/...
As of 345 AM Friday...

Latest surface analysis shows a weak surface trough extending across
the Piedmont of VA into NC with a cold front extending across the
Mid Atlantic into the OH Valley. Other than a few patches of cirrus
clouds, skies are mainly clear with a light southerly surface flow.
The surface trough will strengthen and drop south this morning and
the surface flow across central NC will become west to northwesterly
ahead of the cold front that drops into central NC this evening. The
westerly flow ahead of the front is not a pattern that supports
convection and will keep PoPs limited in the slight chance range and
confined to just the northwestern Piedmont where a disturbance aloft
may initiate some isolated convection across the mountains of WV and
VA the could drop into the northwest tier. A signal for this is
noted in several of the higher resolution CAMs. Highs today will
range in the lower to middle 90s, which may challenge record highs
today which include RDU 95/1944, GSO 93/1915, and FAY 99/1938. Lows
tonight will range in the mid 60s across the northeast to the upper
60s across the southwest, -Blaes
&&

.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
As of 345 AM Friday...

Upper level heights rise slightly across central NC on Saturday. A
weak back door cold front pushes southwest across central NC on
Saturday morning and then stalls near the SC border before washing
out on Saturday night. Low level thickness values drop 15 to 20m
across the northern Coastal Plain from Friday into Saturday morning
with a negligible air mass change near the SC border. Despite the
presence of the front moving across the area in the warm season,
little convection is expected as the air mass is only weakly
unstable and a notable capping inversion is present between 800-700
hPa just atop the surface based mixed layer. Wouldn`t be surprised
to see a few thunderstorms develop from differential heating in the
mountains and slip southeast into the western Piedmont during the
afternoon and evening but coverage and intensity should be limited.
Even with the arrival of a cooler airmass, statistical guidance has
actually trended upward a degree or two from yesterday. Expect highs
to range in the 87 to 94 range. Lows will range from 66 to 72
degrees. -Blaes &&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 240 AM Friday...

Predominantly hot and dry weather is expected through the extended
forecast period. Temperatures will be well above normal for the end
of May with highs in the 90s and lows in the upper 60s to mid 70s.
Normals highs are 80-86 and normal lows are 60-64. The overnight
lows will not provide much of a relief from the persistent heat.
Thankfully, the min RH values will be fairly low, helping to keep
heat indices near the air temperature.

The center of the high aloft will remain anchored over the northern
Gulf Coast as the sub-tropical ridge extends into the Southeast and
Mid-Atlantic. Largely expect the sub-tropical ridge and high aloft
to remain over the aforementioned regions through Tue night/Wed. A
few weak "ridge rider" waves may move over the area, possibly
resulting in some isolated showers. However, the probability of
showers occurring is low at this time. A surface cold front will
extend southwestward into the region from the parent low over New
England, moving through the area Sun/Sun night. This front could
provide enough forcing for showers to develop. Models indicate daily
development of the Piedmont trough over the Carolinas and Virginia
Tue and Wed. There are indications the upper level ridge may break a
bit Wed night/Thu as the upper trough digs southward into the Mid-
Atlantic. The associated surface front will push into the area
Thu/Thu night, resulting the the best chances for showers across
central NC. Temps may also decrease some in the wake of the front
late in the week.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
As of 625 AM Friday...

VFR conditions are expected to dominate across central NC through
the 24 hour TAF period as a ridge of high pressure aloft controls
the weather across the Southeast. A surface trough shifting across
the region will result in a west to northwest low level flow later
today before a mainly dry cold front moves into central NC from the
northeast this evening. A few isolated pockets of fog have developed
this morning which could produce a brief period of MVFR visibilities
this morning. While an isolated thunderstorm is possible this
afternoon and evening, the coverage will be very limited and not
mentioned in the TAF. Light south to southwest winds this morning
will become west to northwest toward midday with some gusts of 15 to
possible 18kts and then northerly this evening. Some periods of high
cirrus clouds are expected through the period with areas of cumulus
clouds with bases around 5kft this afternoon.

Outlook: A ridge of high pressure aloft continue across the Deep
South and Southeast into early next week resulting in generally fair
weather with limited thunderstorm coverage. -Blaes
&&

.CLIMATE...
Here are the record high temperatures and the year they were set for
the period May 24th-29th:

DATE       RDU        GSO        FAY
MAY 24TH   95/1944    93/1915    99/1938
MAY 25TH   93/2011    96/1926    98/2011
MAY 26TH   94/1953    95/1926    98/1926
MAY 27TH   96/1916    100/1911   100/1953
MAY 28TH   99/1941    98/1916    102/1941
MAY 29TH   98/1941    99/1914    102/1941

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...Blaes
NEAR TERM...Blaes
SHORT TERM...Blaes
LONG TERM...KC
AVIATION...Blaes
CLIMATE...RAH