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000
FXUS63 KTOP 151740
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
1240 PM CDT Tue Apr 15 2014

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 302 AM CDT TUE APR 15 2014

Extreme fire danger conditions return for portions of north
central Kansas followed by strong winds and warmer temperatures.

Departing upper trough continues to track eastward over the Mid
Atlantic region as quiet and cold conditions have settled across
northeast Kansas this morning. A quick rebound in temperatures is on
tap for today as variable winds shift to the south, advecting warmer
air into the area. A surface trough, currently positioned over
northern Colorado, deepens eastward this afternoon, increasing
southwesterly winds 15 to 20 MPH west to east after 1 PM across
north central areas. Sounding profilers depict strong mixing through
800 MB across the area, lowering dewpoint temperatures into the
lower 20s and upper teens. Please refer to the fire weather
discussion below for additional details. Have issued a Red Flag
Warning for low humidity and gusty winds for this afternoon into the
early evening across portions of north central Kansas. Highs today
are expected to recover into the upper 50s and low 60s by late
afternoon underneath sunny skies.

Southerly winds increase between 20 and 25 mph sustained this
evening as a strong 60 kt low level jet develops coincident with
the upper trough over the northern plains. The increased mid level
clouds from the passing system and the mixed boundary layer should
keep overnight lows much warmer in the lower 40s.

.LONG TERM...(Wednesday through Monday)
Issued at 302 AM CDT TUE APR 15 2014

Early Wednesday morning, a 60 kt low level jet will be oriented
across the forecast area. While this jet will weaken and gradually
slide to the east, morning mixing will likely bring some rather
strong wind gusts to the surface by 10 AM or so...potentially in
the 45 to 50 mph range. Have not quite gone that high in the
forecast given high cloud cover and a fairly rapid decrease in
wind speeds by late morning, but it is possible. Expect a rather
warm day on Wednesday although a cold front will make its way into
the northwest half of the area by late afternoon. Will likely have
a thermal ridge very near the frontal boundary which would focus
the warmest temps near and just ahead of the front. With the wind,
warm temps, and relatively dry low levels, will have fire weather
concerns for Wed as well...more details in the fire weather
section below.

The front will continue to slowly progress through the area
overnight, although it`s expected to be a dry front through
midnight or so. Beyond midnight, and incoming short wave trough
will interact with the frontal zone as it becomes nearly
stationary near/just south of the forecast area. This will result
in an enhanced area of vertical motion spreading east across KS,
focused mainly across the southern 2/3 of the forecast area.
Expect this to persist through the day on Thursday before the wave
passes overhead on Thursday evening and subsidence takes over.
Expect rather persistent light precipitation with this system. THE
ECMWF is on the dry side of model guidance in terms of total QPF
while it seems that the NAM/GFS are probably picking up on some of
the expected mesoscale lift enhancements and producing slightly
higher amounts. Dry advection from the north will provide a sharp
cutoff to the precipitation, and have reduced POPs in northern KS
with some potential for areas near the Nebraska border to end up
dry if the dry advection is strong enough. Precip type will be
predominantly rain although there seems to be a period early
Thursday morning when it could change to snow especially on the
northern fringes of the precip area. Accumulation appears unlikely
at this time.

Will see a nice warm-up for the weekend as upper ridging returns
to the area on the heels of the Thursday system. Expect moisture
advection to bring dewpoints well into the 50s by Saturday in
advance of the next upper trough. This system has trended slightly
slower over recent model runs but otherwise fairly consistent in
bringing another chance for widespread precipitation to the area.
Do not expect much instability with this storm system but could
still see periods of thunder. This looks to be a pretty widespread
rain with the best chances Saturday night into Sunday, but do not
expect particularly heavy amounts. Should also see continued warm
temperatures throughout the weekend with highs in the upper 60s,
and even warmer behind the system on Monday as little to no cold
advection is expected behind the trough.

&&

.AVIATION...(For the 18Z TAFs through 18Z Wednesday Afternoon)
Issued at 1240 PM CDT TUE APR 15 2014

VFR conditions anticipated. South winds should be taking hold
shortly with surface ridge into Missouri. Speeds increase
overnight with battle between surface decoupling and low level jet
making specifics tricky. At this point think some gust will
occur with fairly steady increases in speed aloft to somewhat
mitigate LLWS despite speeds around 60kt at 2000 feet AGL. Many
area grassland burns but should be plenty of mixing for no
visibility issues.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING until 8 PM CDT this evening FOR KSZ008-020-034.

&&

$$

SHORT TERM...Bowen
LONG TERM...Barjenbruch
AVIATION...65