Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KEAX 240359

1059 PM CDT Thu Apr 23 2015

.SHORT TERM...(This Evening through Sunday)
Issued at 300 PM CDT THU APR 23 2015

The potential for severe storms Friday afternoon and overnight
remains the focus of the forecast. Tonight, warm, moist ascent ahead
of the upper shortwave trough will lead to scattered to perhaps
widespread showers and storms. These storms are not expected to
become severe but will have an important role in how the rest of the
afternoon and evening unfold. Models vary greatly with how this
early activity goes and is dependent upon how far the warm front may
lift. The NAM lifts the warm front into the southwestern portions of
the forecast area, developing a rather robust but localized warm
sector with parameters extremely favorable for severe storms. The
GFS lifts the warm front through much of the area but seems a bit
further west with its ideal combination of instability and shear.
The ECMWF is similar but a bit further west than the GFS. Given the
variability with the warm front placement, the risk for our forecast
area remains conditional. But with most guidance lifting the front
into at least the southern half of the forecast area, the potential
for severe storms, including supercells with large hail, damaging
winds and few tornadoes across the southwestern portions of the
forecast is a very real possibility. Additionally, the boundary
layer looks to be well mixed well into the evening hours and all this
activity will likely grow upscale into a convective system. If the
orientation of this can remain mainly north-south, nearly
perpendicular low-level shear suggest a potential for tornadoes well
into the overnight along with damaging winds.

The other aspect of this storm system will be the potential for
widespread moderate to heavy rainfall mainly north of the Missouri
river. Models are fairly consistent in bringing unseasonably high
precipitable water values, likely in the 90th to average max value
for this time of year. With the strong upper wave providing ample
forcing, there will likely be widespread 1+ inches rain amounts. Some
locations will see more, perhaps several inches more, depending on
where and the nature of the convection. Northern Missouri has been
somewhat dry so far this year, with some recent rains providing some
relief. But overall, flash flood guidance values suggest it can rain
quite a bit before flooding becomes a concern.

.LONG TERM...(Sunday through Thursday)
Issued at 300 PM CDT THU APR 23 2015

Overall...operational models in reasonable agreement that a large
scale upper ridge will build across the western CONUS...while a
downstream upper low slowly meanders across the southern Plains/lwr
Miss Vly early next week. From this vantage point...model progs
indicate much of our region will remain in between the northern and
southern jetstream members...suggesting a fairly dry period through
midweek. Temps through the period should be seasonable with highs
climbing into the upper 60s to lower 70s while lows fall into the
middle to upper 40s.


.AVIATION...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1053 PM CDT THU APR 23 2015

VFR conditions still prevail at the terminals at this late hour, but
they will likely give way to MVFR conditions by sunrise. Expected
scattered showers and thunderstorms to bubble up early this morning.
Looking up stream, thoughts are that early morning activity will be in
the MVFR range. Scattered storms may be able to percolate across the
region throughout the day Friday, though a secondary round of strong
thunderstorms will be possible late in the day and into the evening
hours with the potential for thunderstorms to persist well into
Saturday morning. Currently, thoughts are that most of the activity
should be in the MVFR range. Otherwise, winds will pick up and become
rather gusty through much of the day and into the evening hours.




AVIATION...Cutter is the U.S. government's official web portal to all federal, state and local government web resources and services.