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

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FXUS63 KEAX 052146

346 PM CST Thu Mar 5 2015

Issued at 346 PM CST THU MAR 5 2015

Tonight - Friday:

Our long awaited warm-up starts tonight. A large area of high
pressure extending from WI through east TX will shift east tonight
while pressure falls over the high plains represent the approaching
warm air advection. Looking at a non-diurnal temperature curve over
the western 1/2 of the CWA with an initial quick drop after sunset
and steady to slowly rising temperatures after midnight.

A weak shortwave embedded within broad northwest flow will track
southeast through SD/NE/IA/MO tonight with no impact on sensible
weather. With little moisture to work with should only expecting
some mid clouds across northern MO overnight.

Southwest winds with a pronounced downslope component will yield a
nice warm-up on Friday. Dismissed NAM guidance as its boundary layer
is excessively wet and generates low clouds which greatly impacts
temperatures. This has been a common occurrence during the cold
season. Favor the much drier GFS.

Saturday - Thursday:

Models are in good agreement depicting broad northwest flow aloft
from the Canadian Rockies through the Great Lakes subtly backing
during the period. During this period a positively tilted upper
trough is progged to evolve from the Southern Rockies into the Mid
Atlantic states. Our CWA will be caught in no man`s land with a
couple of non-descript shortwaves embedded within the northwest flow
sending weak cold fronts through, the first one Saturday late
afternoon and the second one Sunday night. However, expect dry
frontal passages with minimal cooling.

Looking more at 925mb temperatures as indicator for degree of warm
air advection as not quite able to mix down from 850mb yet. 925mb
temperatures of 4C-6C should yield above average temperatures over
the weekend. After a minor cool down on Monday models bring back
extensive southwesterly boundary layer winds with 925mb temperatures
from 6C-10C. This should send readings well into the 60s Tuesday
through Thursday, maybe even a few 70 degree readings on Wednesday
if the warmer GFS solution proves true. Not going out on the limb
this far out as confidence is low for that at this time.


.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1139 AM CST THU MAR 5 2015

VFR conditions expected with marginal low-level wind shear conditions
expected late tonight as southwesterly winds steadily increase
at/just above the inversion. KSTJ has best chance of seeing LLWS for
several hours.

Have discounted latest NAM boundary layer moisture profile. Model
tends to over forecast this moisture with retreating surface highs,
especially during the winter. Favor much drier GFS and short range
RAP which maintain clear skies.




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