Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 082048

348 PM CDT THU OCT 8 2015

.SHORT TERM:  (Through Late Tonight)
Issued at 332 PM CDT Thu Oct 8 2015

Looks like this will be a dry FROPA for most of the area tonight.
Short range guidance is in good agreement in developing isolated to
widely scattered showers during the early evening along and ahead of
the front.  Some disagreement though as the evening wears on with
how much the showers will diminish.  The NSSL and NCEP 4km WRF
models are the strongest, keeping a broken line of showers and
thunderstorms together as it moves through the CWFA from northwest
to southeast.  Pretty much every other model weakens the showers and
storms through midnight tonight.  Indeed, MOS PoPs are between 5-15
percent for most of the area.  Have continued the trend of backing
down PoPs, and I now have 30% or less for the entire area.  Cooler
air behind the front will lag behind the wind shift a bit, so I
don`t expect it to play much of a factor in lows tomorrow morning.
MOS lows in the low to mid 50s look pretty reasonable.


.LONG TERM:  (Friday through Next Thursday)
Issued at 347 PM CDT Thu Oct 8 2015

Looks like another stretch of quiet weather in the long-term.  Could
see some lingering showers on Friday along and south of I-44, but
any rain should be more or less done by noon.  High pressure builds
southeast and should be centered over Missouri by 12Z Saturday which
should be our coldest morning of the next 7.  The ridge continues
moving southeast and southwest flow will ramp up quickly Saturday
afternoon.  Temperatures will warm back up above normal Sunday and
will remain at or above normal for the rest of the forecast period.
A strong shortwave will move quickly across the northern CONUS and
southern Canada Sunday night through Monday night.  This will push
another cold front through the area, but the airmass behind the
front won`t be a cold as the airmass moving into the area Friday and
Friday night.   The 12Z runs of the GFS and ECMWF both kick out a
little light QPF ahead of the front, but these are the first runs to
do this.  Additionally, there will be little if any moisture return
ahead of the front so have kept the forecast dry.



.AVIATION:  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1152 AM CDT Thu Oct 8 2015

A cold front extending from a surface low in northwestern
Wisconsin southwest through southeastern Nebraska will move
southeastward through the taf sites this evening. The cold front
should move through STL around 05Z tonight. The swly surface wind
will veer around to a nwly direction after fropa. There will
likely be a broken line of showers along and just behind this
front. For now will just include VCSH in the UIN and COU tafs for
early evening, and for the St Louis metro area late this evening
into the overnight hours as it appears that most of the showers
should be on the light side with only scattered coverage. Post
frontal low level cloudiness can be expected Friday morning,
possibly briefly dropping into the MVFR catagory.

Specifics for KSTL: Will continue with VCSH in the STL taf for
late evening into the overnight hours as scattered, mainly light
showers are expected as a cold front moves through the area. The
swly surface wind will veer around to a nwly direction late
tonight after fropa. Post frontal, low level cloudiness can be
expected on Friday, possibly dropping into the MVFR catagory for a
brief period of time.



Saint Louis     60  66  50  70 /  30  20   0   0
Quincy          55  64  45  69 /  30  10   0   0
Columbia        55  66  46  72 /  30  10   0   0
Jefferson City  56  66  46  71 /  30  20   0   0
Salem           59  67  48  68 /  30  20   0   0
Farmington      57  64  47  67 /  30  30   0   0




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