Area Forecast Discussion
Issued by NWS St. Louis, MO

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199
FXUS63 KLSX 040803
AFDLSX

Area Forecast Discussion
National Weather Service Saint Louis MO
303 AM CDT WED MAY 4 2016

.SHORT TERM...  (Through Late This Afternoon)
Issued at 300 AM CDT Wed May 4 2016

Main focus for today will be temps.

At the beginning of the period this morning, 12z, the cdfnt is
expected to be approx half way thru the CWA. As the fnt pushes S,
winds increase and become nnwly behind the fnt. Deep mixing behind
the fnt, and ample insolation, will help offset the CAA and shud
still allow temps to warm into the mid to upper 60s. Going forecast
may in fact still be too cool, especially across the ern half of the
CWA where few if any clouds are expected.

Ongoing SHRA ahead of the fnt continues to quickly push swd early
this morning. These SHRA shud be exiting the sern portions of the
CWA around sunrise. The question then turns to chances this
afternoon. Believe that better chances for SHRA will remain E of the
area, but have kept mention of isod SHRA for early to mid this
afternoon as a vort max rotates around the upper low. Can also not
rule out TS given the steep lapse rates with some CAPE suggested by
guidance.

Tilly

.LONG TERM...  (Tonight through Tuesday)
Issued at 300 AM CDT Wed May 4 2016

Surface ridge to slowly build in across region tonight and
remain over the area through Friday. Will see dry and cooler weather
with lows in the 40s and highs in the mid to upper 60s on Thursday,
warming up into the 75 to 80 degree range on Friday.

Surface ridging to begin moving off to the east by Saturday as next
weather system approaches the region. Models are a bit faster with
developing a warm front over northern portions of forecast area on
Saturday with increasing low level moisture and convergence along
the boundary, so could see some elevated convection fireup by
Saturday afternoon and persist through the rest of the forecast
period as front stalls out over region. It will not be a continuous
rain event, but will see several rounds through out the rest of the
forecast period. The warmest day will be Saturday with highs in the
upper 70s to mid 80s, then dip down to near normal temps as frontal
boundary settles a bit further south along the I-70 corridor.

Byrd
&&

.AVIATION...  (For the 06z TAFs through 06z Wednesday Night)
Issued at 1056 PM CDT Tue May 3 2016

An upper level disturbance over the Great Lakes region will send
a cold front southeastward through the taf sites late tonight and
Wednesday morning. A band of VFR, low-mid level cloudiness will
advect southeastward through the area along the front. A band of
showers will also drop southeastward through IL late tonight and
Wednesday morning with the western edge likely impacting UIN and
the St Louis metro area between 06Z and 12Z. Will include a 3
hour tempo group for light showers in these tafs. Southwest wind
will veer around to a northwesterly direction late tonight and
early Wednesday morning after fropa and become relatively strong
and gusty Wednesday morning. There may be scattered diurnal
cumulus clouds in UIN and the St Louis metro area late Wednesday
morning and afternoon which will dissipate Wednesday evening.
The surface wind will diminish Wednesday evening as a surface
ridge over the northern Plains builds southeastward into MO.

Specifics for KSTL: VFR, low-mid level cloudiness will advect
south-southeastward into STL late tonight. A band of light
showers will drop south-southeastward through STL between 09-12Z
Wednesday. Will include a tempo group for light showers in the
STL TAF during this time frame. The southwest wind will strengthen
late tonight as the surface pressure gradient tightens, then veer
around to a northwest direction early Wednesday morning after
fropa and become gusty. Scattered diurnal cumulus clouds are
possible late Wednesday morning and afternoon which will dissipate
Wednesday evening. The surface wind will diminish Wednesday
evening.

GKS
&&

.FIRE WEATHER...
Issued at 300 AM CDT Wed May 4 2016

Will continue to see a heightened fire danger this
afternoon over central and southeast Missouri because of low RH,
between 25 and 30 percent, gusty northwest winds and dry fuels.

Byrd
&&

.PRELIMINARY POINT TEMPS/POPS...
Saint Louis     68  46  67  50 /  20   5   0   0
Quincy          65  42  67  49 /   5   0   0   0
Columbia        68  44  69  49 /   5   0   0   0
Jefferson City  70  44  70  48 /   5   0   0   0
Salem           65  44  65  47 /  60   5   0   0
Farmington      68  44  67  44 /  20   5   0   0

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

$$
WFO LSX



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