Area Forecast Discussion
Issued by NWS Springfield, MO
FXUS63 KSGF 011102
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
602 AM CDT Wed Oct 1 2014
...12z Aviation Forecast Update...
.SHORT TERM...(Today and Tonight)
Issued at 233 AM CDT WED OCT 1 2014
Surface moisture will increase today ahead of the next storm
system to affect the Missouri Ozarks. Surface dewpoints in the upper
60s were noted across central and southern Oklahoma and that rich
airmass will be moving in late today and tonight. There is a wave
ejecting out across the central Plains region this morning shown
on the latest water vapor imagery. This will help develop
convection mainly across eastern Kansas into northwestern
The area north and west of I-44 is currently highlighted
in a slight risk from SPC for later today and tonight. With strong
instability forecasted with CAPE values approaching 2000
J/KG...Bulk Shear at 40 knots...25 knot low level shear...and
Storm Relative Helicity between 200 to 300 M2/S2...Low Level CAPE
around 50 to 75 J/KG...A few supercells will be possible across
portions of southeast Kansas into west central Missouri with the
main threats being very large hail up to the size of golf balls
and damaging wind gusts to 65 mph. Given the low level
environment...there will be a threat for an isolated tornado or
two late this afternoon into the early evening hours.
This convection will merge into a cluster as it moves slowly
northeastward into central Missouri by tonight. Some training of
storms are possible with locally heavy rainfall and there will be a
limited flooding risk tonight through Thursday night.
.LONG TERM...(Thursday through Tuesday)
Issued at 233 AM CDT WED OCT 1 2014
The main episode of the potential for severe weather will be
Thursday afternoon into Thursday evening. This system is currently
located just southwest of Salt Lake City. This wave is much strong
and will move out across the central and southern Plains region
Potential CAPE values will approach 3000 J/KG with Bulk shear around
40 knots. Mid level speed max will move across the area late
Thursday afternoon. Low Level Cape values will approach 100 J/KG and
SRH will be about 300 M2/S2.
The latest thinking is all modes of severe weather will be
possible Thursday afternoon into the evening. Initial discreet
convection will develop across eastern Kansas and northeast
Oklahoma and move northeastward eventually merging into a squall
line by the time it reaches the I-49 corridor. The main threat
Thursday afternoon and evening will be damaging winds with an
extensive squall line. The environment may be conducive for a
tornado or two with even with the squall line as it moves eastward.
Large hail will be possible too.
Heavy rainfall will be possible with the greatest rainfall totals
along and north and west of I-44 and west of Highway 65 where 1 to
3 inches may fall. Areas east southeast of I-44 will generally be
up to an inch. There will be a limited flash flooding risk north
and west of I-44 through Thursday night.
The cold front sweeps through late Thursday night and a much
colder Canadian airmass moves in. Forecasted 850 mb temperatures
will near 0 Celsius by late Friday which is chilly. The latest
guidance has come in colder and will trend that way with this
forecast update. Friday will be a shocker compared today...Friday
will be mostly cloudy...windy...much cooler with high temperatures
only in the upper 50s to lower 60s.
The center of the surface high will be near or just west of our
area late Friday night into Saturday morning. Surface dewpoints
will be in the lower 30s with actual temperatures now forecast to
be in the upper 30s and possibly mid 30s in the colder spots. With
that said...will start mentioning the potential of a least patchy
frost Friday night. As confidence increases...will have to fine
tune the temperatures and the frost potential but it is something
to think about looking at the models.
The area will stay in a west-northwest flow for the weekend into
early next week. Seasonable temperatures will stay around and dry
weather. There will be a gradual warming trend as we look into the
middle of next week. The models are in disagreement by the middle
of next week with the next weather system.
.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 554 AM CDT WED OCT 1 2014
There only aviation concern for pilots flying in and out of the
Missouri Ozarks region through the next 24 hours will be convection
developing late this afternoon into the evening hours. This will
be mainly for JLN and SGF. Have included a PROB30 group for this
chance of scattered convection to impact the terminals. Winds will
become breezy and gusty today with south winds gusting up to 20
knots. Mainly VFR will prevail with the exception of any
convection briefly impacting terminals with brief visibility drops.