Area Forecast Discussion
Issued by NWS St. Louis, MO
FXUS63 KLSX 301758
AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1258 PM CDT Sat May 30 2015
.SHORT TERM: (Through Monday)
Issued at 309 AM CDT Sat May 30 2015
Cold front stretching from Wisconsin to Kansas will continue to
press southeast today as one last potent shortwave rotates northeast
across the region. PWATS will approach 2 inches ahead of the cold
front, which means showers and thunderstorms will continue to be
very efficient rain producers. Adjusted and extended the Flash Flood
Watch to align with areas that are expected to see the greatest
amounts of rain and convection through this evening, generally the
southeastern half of the CWA.
Still believe measurable preciptiation will shut down quickly this
evening from west to east with only some lingering drizzle and
patchy fog possible overnight. Temperatures will certainly be cooler
behind this front with lows in the 50s and highs only in the 60s on
Sunday and lower 70s on Monday.
.LONG TERM: (Monday Night through Friday)
Issued at 309 AM CDT Sat May 30 2015
Temperatures will continue to warm up to near normal levels for
the first part of the work week as the surface ridge moves east
and an upper level ridge tries to build across the Plains into the
Mississippi Valley. While the flow aloft remains northwesterly,
low level flow becomes southerly by Thursday which should allow
some moisture to return to the area. Additionally, the 850mb
thermal ridge builds up across the area Thursday into Friday which
looks to allow temperatures to warm above normal for the end of
the week. Medium range models show a couple of shortwaves trying
to move around the periphery of the upper level ridge from the
middle of the week through Friday, spitting out some light QPF as
they move across the area. Can`t rule out scattered thunderstorms
as this occurs due to the increasing moisture from southerly flow
in the low levels, so slight chance to low chance PoPs provided by
ensemble guidance looks pretty reasonable.
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1228 PM CDT Sat May 30 2015
Specifics for KCOU: Light to moderate rain showers will linger in
the vicinity of KCOU for the next few hours. Prevailing flight
conditions should fall to IFR tonight due to nocturnal cooling and
plenty of moisture in the lower atmosphere. Only slow improvement
is expected tomorrow morning.
Specifics for KUIN: A band of moderate rain showers was moving
through KUIN at TAF issuance, but should be just south of the
terminal by 18z. Showers continue in the vicinity for the next few
hours before tapering off. Prevailing flight conditions should
fall to IFR tonight due to nocturnal cooling and plenty of
moisture in the lower atmosphere. Only slow improvement is
expected tomorrow morning.
Specifics for KSTL: Light to moderate rain showers will continue
through most of the afternoon. Ceilings will most likely vary
between IFR and MVFR. Although prevailing flight conditions
should improve to MVFR for a few hours later this afternoon,
cloud bases quickly drop back to IFR tonight due to nocturnal
cooling and extensive moisture in the lower part of the
atmosphere. Only slow improvement is expected tomorrow morning.
MO...FLASH FLOOD WATCH until 7 PM CDT this evening FOR Crawford MO-
Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Lincoln MO-
Madison MO-Montgomery MO-Reynolds MO-St. Charles MO-St.
Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve
MO-Warren MO-Washington MO.
IL...FLASH FLOOD WATCH until 7 PM CDT this evening FOR Bond IL-
Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Randolph IL-St. Clair IL-Washington IL.