Area Forecast Discussion
Issued by NWS Springfield, MO

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FXUS63 KSGF 191121

621 AM CDT Tue Aug 19 2014

.SHORT TERM...(Today and Tonight)
Issued at 253 AM CDT TUE AUG 19 2014

A loosely organized cluster of showers and thunderstorms will
continue to spread east into the Missouri Ozarks early this
morning. We expect this activity to survive until at least U.S. 65
as the incoming system cold pool and a veered low level jet
continue to promote new updrafts along the eastern/southeastern
flank of this cluster. Although deep layer shear is rather weak
across the region, instability remains rather robust which will
support a few updrafts putting down mainly sub-severe hail. The
system cold pool with this cluster is not all that strong, so we
do not believe it poses a severe wind threat. A localized gust
over 50 mph will still be possible with any stronger individual
cells within the cluster.

As we get from mid-morning onward, the fate of this convection is
in question. It is possible that it takes a turn south and
follows the better instability into eastern Oklahoma/western
Arkansas. It is also possible that it just slowly dissipates as it
outruns better instability east of U.S. 65. We will have to watch
for some renewed development this afternoon across the eastern
Ozarks along any outflow boundaries. The morning convection and
remnant cloud cover could have a play on high temperatures this
afternoon. Current thinking is that the convection and clouds will
exit fast enough to allow us to warm up to temperatures similar
to, or even slightly warmer than those of Monday afternoon.

We are then expecting more thunderstorm development later tonight
across the Corn Belt as a broad low level jet stream impinges on
a low level frontal boundary. It is possible that some of this
activity could clip central Missouri late tonight, but most of it
should remain across northern Missouri. Otherwise, dry conditions
are expected.

.LONG TERM...(Wednesday through Monday)
Issued at 253 AM CDT TUE AUG 19 2014

Long wave charts then continue to indicate that a long wave ridge of
high pressure will strengthen from the Mid-South up into the
Appalachian States. This pattern will favor a synoptic scale ridge
strengthening over the Lower and Middle Mississippi Valley. Hot
conditions are therefore expected for the Missouri Ozarks from
midweek through the upcoming weekend. Highs in the middle to upper
90s are expected with lows in the lower to middle 70s.

One item that we remain a bit unclear on is surface dew points and
resultant heat indices. The synoptic scale pattern does show low
level moisture trajectories off of the western Gulf of Mexico, but
any moisture advection would initially stream into the southern
Plains before then advecting northeast into the Ozarks.
Interestingly, patterns such as this can promote fairly high mixing
heights. This would support the potential to mix down drier air to
the surface in the afternoons, especially along the higher terrain
of the Ozark Plateau. With that being said, we have generally kept
afternoon heat indices in the 97 to 104 degree range for now.

Long wave charts then indicate that the ridge may lose some
amplitude and shift slightly east early next week. This may open the
door to a front slipping into the region and slightly cooler


.AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 616 AM CDT TUE AUG 19 2014

The convection over western Missouri seems to be on a downward
trend. As such...will remove mention altogether for KSGF and only
mention VCSH for KJLN til mid morning.

After that...expect VFR conditions through the remainder of the
forecast period. Winds could be a little gusty at KSGF and KJLN
from late morning through early evening.




SHORT TERM...Schaumann
LONG TERM...Schaumann
AVIATION...Gaede is the U.S. government's official web portal to all federal, state and local government web resources and services.