Area Forecast Discussion
Issued by NWS St. Louis, MO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KLSX 090434
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1134 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
tonight.

Tilly

.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.

Britt

&&

.AVIATION:  (For the 06z TAFs through 06z Wednesday Night)
Issued at 1130 PM CDT Tue Jul 8 2014

VFR flight conditions will prevail through the forecast period. A weak
front/secondary push of drier air will move into the region overnight
into Wednesday morning, with high pressure settling into Missouri
in the wake of the front. Clouds will be limited to diurnal cu.

Specifics for KSTL:

VFR flight conditions will prevail through the forecast period. A weak
front/secondary push of drier air will move into the region overnight
into Wednesday morning, with high pressure settling into Missouri
in the wake of the front. Clouds will be limited to diurnal cu.

Glass

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.