Area Forecast Discussion
Issued by NWS Springfield, MO
FXUS63 KSGF 241728
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1228 PM CDT Fri Apr 24 2015
Issued at 626 AM CDT FRI APR 24 2015
Narrow band of convection has finally fired across portions of
southeastern Kansas, northeastern Oklahoma and northwestern
Arkansas. Isentropic upglide in the 300-310K layer matches up
nicely with current placement and timing of convection. The lift
isn`t all that strong, but certainly good enough given 400-800
J/kg of elevated CAPE. This activity is moving into a slightly
more hostile environment, with dry air at the midlevels and
lessening CAPE. That said, this activity is bringing its own
moisture to the party for the time being and should be sustained
well into southwestern Missouri this morning. Low level easterly
flow over central Missouri and the eastern Ozarks will be a bit
more formidable to overcome, as a result showers/storms should
become more diffuse and weaken in this area during the mid/late
Given marginal CAPE and instability, severe weather is not
expected this morning. That said, the occasional perky updraft
will yield small hail from time to time.
Will continue to massage PoPs this morning for timing.
.SHORT TERM...(Today and Tonight)
Issued at 312 AM CDT FRI APR 24 2015
Breezy southeast winds ahead of an approaching warm front are
helping to keep temperatures rather mild this morning, with readings
only falling into the low to mid 50s as of 3 AM. While the surface
warm front remains well to our southeast, the 925 and 850 fronts are
starting to lift northeast over the region this morning, and short
term guidance continues to suggest that the associated isentropic
ascent will eventually result in showers and thunderstorms
developing across the region closer to daybreak. While a smattering
of hail will be possible with any of these elevated thunderstorms,
the overall severe weather risk this morning appears quite low.
Convection that develops during the pre-dawn hours will push east
during the morning today, with additional activity possibly moving
in from Arkansas later this morning into this afternoon. Confidence
in the coverage of this southern activity is low, however, and it`s
quite possible that the afternoon hours end up being dry for many
By late afternoon and early evening, convection should then fire
along the dryline across central Kansas and Oklahoma, as well as in
the vicinity of the triple point, which will likely be located
somewhere in the vicinity of Topeka, KS. The overall trend in
guidance over the last 12-24 hours has been to keep the dry line
further west through the afternoon and evening hours, suggesting
that it may take some time this evening/tonight before convection
arrives in the SGF CWA. This overall trend has been noted by SPC
with their Day 1 Outlook, which now only includes extreme western
Missouri and southeastern Kansas in the Slight Risk area.
In all likelihood, convection will arrive late this evening into the
overnight hours in the form of several clusters/areas of activity.
Shear isn`t an issue with this system, so we will need to carefully
watch for any supercell structures, as well as any line segments
that bow out to the east for a conditional wind/tornado threat.
Steep mid level lapse rates will lend themselves to a threat for
hail, though overall lackluster instability will probably limit this
.LONG TERM...(Saturday through Thursday)
Issued at 312 AM CDT FRI APR 24 2015
The surface low will then push east across central Missouri during
the morning hours Saturday, with the associated cold front sweeping
across the forecast area. We will likely see convection strengthen
and/or redevelop along the front as it moves across the CWA, with
any associated severe threat highly dependent on frontal
speed/timing. Slower timing will give areas ahead of the front a
better opportunity to destabilize, while quicker fropa may keep the
bulk of the convection to our east.
High pressure will nose into the area on Sunday, and with a bit of
shortwave ridging aloft, it doesn`t look like a bad end to the
weekend, with dry conditions and temperatures generally in the 60s.
Rain chances will then return to at least far southwestern Missouri
Monday and Tuesday, as a shortwave diving south across the Great
Basin closes off and slowly tracks east across the southern Plains.
Right now it looks like the forecast area will be on the northern
edge of the rainfall, though any shift north or south with the
system will have a significant impact on rain chances, so stay
Beyond Tuesday, the region looks to once again be situated on the
western edge of the Great Lakes/eastern CONUS trough, resulting in
generally dry conditions and seasonable temperatures.
.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 1221 PM CDT FRI APR 24 2015
A broad are of low to mid clouds was affecting much of the plains
and the Ozarks region this afternoon as a storm system over the
western plains move towards the region. This will keep the region
under MVFR ceilings along with gusty surface winds from the
southeast into this overnight hours. Low level wind shear will
impact all terminals as strong low level winds moves through the
Slowly improving skies becoming VFR by mid morning Saturday are
expected as surface winds shift out of the southwest and remain
gusty at times.