Area Forecast Discussion
Issued by NWS Springfield, MO

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FXUS63 KSGF 211157

657 AM CDT Thu May 21 2015

.SHORT TERM...(Today and Tonight)
Issued at 209 AM CDT THU MAY 21 2015

Stratus/low clouds/drizzle continue in wake of the earlier
shortwave passage yesterday. The unseasonably cool and rain
moistened low level air mass in place and a lack of significant
subsidence to erode the stratus from above has kept the dreary
weather in place.

Rising mid level heights with a building upper ridge over the
Plains and increasing subsidence combined with a higher May sun
angle should eventually erode the low clouds from above and
below, but the process almost always seems to take longer than
expected. For the fcst database/grids will keep conditions cloudy
for much of the morning with a gradual transition to sct-bkn

Temperatures will hinge on the sky clearing and it may be a slow
start to the diurnal temperature rise. Went with a blend of MOS guidance.

Sfc high pressure will move in from the wnw becoming centered over
the area by late afternoon and tonight. Light winds and a drier
air mass will allow temperatures to drop quickly this evening then
bounce around. Could actually see some upper 30s in some hilly
micro-climates in the eastern cwfa if higher clouds are not
extensive. Could also see some shallow fog in favored lower/valley

.LONG TERM...(Friday through Wednesday)
Issued at 209 AM CDT THU MAY 21 2015

Potential weather impacts will be gradually increasing rainfall
amounts and possible flooding Sunday-early Tue.

An upper level long wave west coast trough, with smaller scale
circulations pinwheeling around it, is still progged to gradually
shift east slowly into the Rockies over the weekend. A downstream
ridge extending from FL and the eastern Gulf of Mexico into the MS
Vly will help keep the bulk of any precip off to the west and
southwest Fri and early Sat, although some pops are warranted for
the w-sw cwfa as moisture does begin to advect into the region.

Eventually the upper ridge shifts east and with mid level height
falls and better overall lift (along with any smaller scale short
wave features). Periodic rain/tstms chances will increase
Sat night-Sunday into Monday as stronger low level winds bring up
increased Gulf moisture. Model trends seem to be slowing down the
timing a bit with the upper ridge over the southeast U.S. building
and remaining in place and the long wave trough to our west also
slowing a bit, but only have generally minor changes from the
previous forecast. General forecast rainfall of 2+ inches are in
the grids from Sat night-Tue in counties along and west of I-49.

Eventually will have to consider watch headlines for the western
cwfa if the forecast holds, but after coordination with some
surrounding offices agreed to hold off since widespread adverse
impacts are expected later in the weekend (Sunday- Mon-maybe
early Tue).


.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 647 AM CDT THU MAY 21 2015

Flight conditions ate area terminals will see slow improvement
through the morning and into the afternoon as high pressure moves
across the plains and into the Ozarks. Initially MVFR ceilings will
improve to VFR as skies clear this afternoon and remain clear
through the overnight tonight.




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