Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 081845

145 PM CDT Tue Jul 8 2014

.SHORT TERM:  (Through Tonight)
Issued at 132 PM CDT Tue Jul 8 2014

Focus tonight will be precip chances. Latest guidance suggests the
narrow CU field that is currently across the srn third of the CWA
may continue to develop and produce an isod TSRA over the next
couple of hours. If storms develop, they shud quickly sink S of
the CWA this afternoon. Have kept slight chance PoPs for the far
srn portions of the CWA to account for uncertainty in timing and
placement for any storms that develop this afternoon.

Otherwise, with cooler dewpoints advecting into the region and
anticipating a clear sky, have trended twd the cooler guidance for


.LONG TERM:  (Wednesday through Next Tuesday)
Issued at 132 PM CDT Tue Jul 8 2014

(Wednesday through Friday)

Wednesday and Thursday still look like dry days as the new runs of
the NAM/GFS show that we will lie under subsidence in the
northwesterly flow aloft.  At the surface, high pressure will move
across the area Wednesday and early on Thursday.  MOS temperatures
are in good agreement the next few days, and see no reason to
deviate from them.

By Friday, it still looks like a warm front will move through the
area from the west in response to a shortwave trough dropping
southeast across the Midwest.  The ascent from the shortwave
combined with low level moisture convergence along the front
should be enough to keep the chance of showers and thunderstorms
going over the CWA.  The greatest chance will be in the north where
the ascent will strongest with the shortwave.

(Saturday through next Tuesday)

The GFS and ECMWF are showing the upper flow becoming more amplified
today in the extended part of the forecast with a ridge in the west
and a trough in the east.  The upper flow will be becoming more
northwesterly with time.  It looks like a front will move into the
area over the weekend bringing a chance of thunderstorms to the
area.  850mb temperatures ahead of the front will be around
20C...though they may be tempered by the clouds and rain chances.
Both models show the front moving south of the area by late Monday
and Tuesday with the ECMWF temperatures falling to around 10C by
Tuesday evening.



.AVIATION:  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1220 PM CDT Tue Jul 8 2014

Current cigs will break up and become sct this afternoon. Expect
the remainder of the TAF period to be VFR. Winds will diminish and
back slightly this evening and become nwly again Wed morning. Only
expect diurnal CU Wed morning. Some guidance is suggesting that FG
may develop and impact UIN/COU late tonight. While the rainfall
last night may support this, believe enuf mixing will persist
tonight to prevent FG development.

Specifics for KSTL: VFR and dry conditions are expected thru the
period. Cigs are expected to quickly break up this afternoon with
winds remaining nwly this afternoon. Winds will diminish and back
slightly this evening and become nwly again Wed morning. Only sct
diurnal CU is expected Wed.



Saint Louis     87  65  84  64 /  10  10   5   0
Quincy          83  61  79  60 /  10  10   5   0
Columbia        86  61  82  63 /  10  10   5   5
Jefferson City  86  61  83  63 /  10  10   5   5
Salem           84  63  82  61 /  30  10   5   0
Farmington      86  62  82  61 /  30  10   5   5




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