Area Forecast Discussion
Issued by NWS St. Louis, MO
FXUS63 KLSX 010746
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
246 AM CDT THU OCT 1 2015
.SHORT TERM: (Through Late This Afternoon)
Issued at 245 AM CDT Thu Oct 1 2015
Early this morning, northwest flow aloft prevails with an upper
level disturbance over southern IL, slowly moving away from our
region to the southeast. All of what this disturbance is producing
is all on its eastern flank (southeast IL) with clouds and some
evidence of a few sprinkles as well. At the surface, Canadian high
pressure is steadily building and settling in to our region, with
northeast surface winds bringing more autumnlike air, as temp
readings dip into the 40s and low 50s. Otherwise, the sky was clear
across much of our region other than a few clouds edging the far
eastern portion around Salem, IL.
Northwest flow aloft will carry the upper level disturbance away
from our region, and surface high pressure will dominate,
resulting in NE winds and a dry atmospheric column. Despite a lot
of clouds existing just to the east and there is flow aloft from the
east currently, this will all change over the next few hours as the
upper level disturbance pulls out and will limit how far west these
clouds will be able to go this morning. Otherwise, the only clouds
expected today are some scattered diurnal cumuliform that will
probably initially begin east of the MS river and expand some to
west of the river late in the day before dissipating by evening.
Prefer the higher MOS values for max temps today, considering the
high levels of sunshine, and this will give us readings a few
degrees below persistence, or 65 to 70F.
.LONG TERM: (Thursday through Next Wednesday)
Issued at 239 PM CDT Wed Sep 30 2015
Have continued a cool and mostly dry forecast thru the middle of
next week. Sfc ridge currently building into the region is expected
to remain in control of the weather pattern thru early next week.
Mdls are in good agreement with this aspect. Have generally a
persistence temp forecast.
Differences among mdl solns begin to manifest by Fri. The s/w
currently over IA is progd to dig into the sern U.S. and develop
into a cut off low. Latest solns regarding this cut off low and how
it interacts with Hurricane Joaquin suggest it will not have much of
an impact on the region. At most it seems may provide additional
cloud cover, stronger winds and therefore, cooler temps.
Regardless, latest guidance suggests a trof and associated sfc
wave/fnt bringing a chance for precip late Tues into Wed. Given the
performance with the last fnt, will keep PoPs low, anticipating isod
to widely sct coverage attm.
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1138 PM CDT Wed Sep 30 2015
Building high pressure will keep VFR conditions across the region
with a north-northeast wind.
Specifics for KSTL:
VFR conditions expected.
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 69 45 66 48 / 0 0 0 5
Quincy 66 42 64 44 / 0 0 0 5
Columbia 67 43 66 44 / 0 0 0 5
Jefferson City 68 44 66 45 / 0 0 0 5
Salem 69 46 65 48 / 0 0 10 20
Farmington 67 43 64 45 / 0 0 5 5