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Area forecast discussion...updated 
National Weather Service St Louis MO
942 PM CDT Friday Oct 9 2015

issued at 933 PM CDT Fri Oct 9 2015

Low clouds are slowing clearing/decreasing southward this evening and
overnight will push more to the southwest as low level winds
veering some from northerly. In the wake of the low clouds a swath
of high clouds will move into the area from the northwest and be
centered across southeast MO and southern Illinois at daybreak. All in
all the southern portion of the County Warning Area is likely to see predominately
cloudy skies tonight and the warmest temperatures. Will be making
some adjustments to the cloud cover trends and amounts, and lows
in the northern County Warning Area.



Short term: (through late tonight)
issued at 151 PM CDT Fri Oct 9 2015

Deepening shortwave diving southeast across the middle Mississippi
River valley into the southeast Continental U.S. Has provided cloud cover and
some showers in the wake of the cold front that moved across the
region last night. Back edge of stratus expected to steadily March
southeast with surface high pressure building south from the upper
Midwest and plains. Temperatures will be slow to drop until
clearing occurs and therefore have a gradient with low
temperatures ranging from the lower to middle 40s across the
northwest to lower 50s in the southeast.


Long term: (saturday through next friday)
issued at 151 PM CDT Fri Oct 9 2015

High pressure will help produce perfect weather on Saturday with
sunny conditions and mild temperatures in the upper 60s to lower
70s. Southwest wind will develop in the wake of the high on Sunday
and temperatures will respond with highs jumping back into the
upper 70s to lower 80s areawide.

Appears the week will see a roller coaster ride of temperatures as
area remains under northwest flow aloft and is dealt a steady diet
of dry cold frontal passages. First cold front arrives late
Sunday night, another late Tuesday night, and another Thursday
afternoon. The airmass behind each of these fronts will be of
Pacific origin so do not expect any significant cool Downs, but
rather a return to near normal values. No signal of signficant
precipitation the next seven days.



Aviation: (for the 00z tafs through 00z Saturday evening)
issued at 523 PM CDT Fri Oct 9 2015

Surface ridge extending from southern Minnesota southwest through
central Kansas will shift southeastward through the taf sites late
tonight and Saturday morning. North-nwly surface winds will become
light later this evening. The low level cloud cover around
3000-4000 feet in height will clear out from northwest to
southeast tonight with increasing subsidence. The clouds will
clear out of uin and cou this evening, and in the St Louis Metro
area around 06z late tonight. There will likely be some radiation
fog in cou late tonight/early Saturday morning, and steam fog in
the river valleys due to cold air over the warmer river water
which will impact sus and cps late tonight/early Saturday morning.
The light surface wind will become S-swly in uin and cou by
Saturday afternoon as the surface ridge shifts southeast of this

Specifics for kstl: the low level cloud ceiling around 4000 feet
in height will clear out around 06z later tonight with the
clearing line advancing from the northwest. The N-nwly surface
wind will diminish and become light by late tonight.



Preliminary point temperatures/pops:
Saint Louis 50 70 54 80 / 0 0 0 0
Quincy 46 69 51 80 / 0 0 0 0
Columbia 46 71 52 82 / 0 0 0 0
Jefferson City 45 72 51 83 / 0 0 0 0
Salem 50 67 49 75 / 0 0 0 0
Farmington 48 66 49 76 / 0 0 0 0


Lsx watches/warnings/advisories:


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