Area Forecast Discussion
Issued by NWS Topeka, KS

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000
FXUS63 KTOP 292010
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
310 PM CDT Sun Mar 29 2015

.SHORT TERM...(This Evening through Monday)
Issued at 310 PM CDT SUN MAR 29 2015

19Z water vapor imagery show a shortwave trough passing east of the
upper MS river valley with shortwave ridging moving into the
northern plains. A frontal boundary has moved through much of the
forecast area with temps warming behind the front due to good mixing
of the boundary layer and no cold air behind the front.

For tonight and Monday, the weather should be pretty nice with a
relatively dry airmass moving in and no obvious forcing or lift to
generate any precip. Weak surface ridging and clear skies tonight
look to set up some decent conditions for radiational cooling.
Because of this have tended to go with the coolest MOS guidance or a
degree cooler. Think lows will generally be in the mid 30s. This
weak ridge moves east of the area during the day Monday allowing
south and southwesterly winds to pick up and advect some warmer air
into the region. There looks to be good mixing of the boundary layer
again so highs in the lower to mid 70s appear on target and have not
made any major changes to the going forecast. Winds may become
breezy in the afternoon and cause additional fire weather concerns.
See the fire weather discussion for a more detailed discussion about
these concerns.

.LONG TERM...(Monday Night through Sunday)
Issued at 310 PM CDT SUN MAR 29 2015

Weak boundary still anticipated to settle into eastern Kansas Monday
night with westerly flow over it allowing for even warmer temps for
Tuesday. Local area becomes increasingly impacted by the next upper
wave translating east from the Pacific Northwest into the Great
Lakes Tuesday night into Thursday. Increasing south to southwest
winds Tuesday night into Wednesday bring higher theta-e air in, but
also likely a minor capping inversion over it as well. Moisture
return looks slow and meager enough to keep anything elevated in
check for Tuesday night with lows only in the upper 40s to middle
50s. Cold front`s progression continues to trend slower, likely
leaving most locations dry through the late afternoon with highs now
pushing into the lower 80s. 12Z ECMWF has now sped up the front for
Wednesday night however, leaving this period as the main opportunity
for precipitation in this forecast. Mid-level lapse rates in the 7.5
to 9 C/km range and moderate shear still provide at least minor
concern for severe weather Wednesday night. The timing of the
secondary upper wave remains troublesome Thursday night into Friday,
but at least some chance for elevated showers and perhaps a few
thunderstorms remains with cyclogenesis to the southwest keeping the
elevated front nearby. Lower level cold air advection Thursday into
Friday brings temps down, though just how far is uncertain. Have
values in the middle of most spreads at this point. Modification
should occur for the weekend with rising mid/upper heights and south
winds returning.

&&

.AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon)
Issued at 1156 AM CDT SUN MAR 29 2015

Dry air moving in and forcing moving out will lead to VFR
conditions.

&&

.FIRE WEATHER...
Issued at 310 PM CDT SUN MAR 29 2015

In spite of some good mixing across north central KS this afternoon,
dewpoints have held in the lower 30s for the most part. One does not
have to look very far north and west to see dry air that could still
advect into the red flag warning area. Because of this think there
is still the potential to see RH values drop this afternoon and will
maintain the warning as is.

For Monday, southwest winds are expected to become breezy as high
pressure slides east. Wind gusts could be as high as 25 or 30 MPH.
Although the low level moisture will again be the main uncertainty. At
this time have dewpoints mixing out and staying in the lower to mid
30s in spite of the model solutions advecting 40 degree dewpoints
into the area. There are signs from the forecast soundings of some
low to mid level moisture advection ahead of the weak surface
boundary which cold help to keep humidity levels up. Thinking is the
moisture advection will be later in the day and boundary layer
mixing could bring the dry air to the surface ahead of the moisture
advection. With highs in the lower and mid 70s, this would yield min
RH values in the 20 to 25 percent range. However feel like if the
forecast is going to be off, it is on the dry side and low level
humidity may actually be a little higher due to that moisture
advection. Nevertheless even if low level moisture is higher, the
grassland fire danger is likely to remain very high for Monday.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING until 7 PM CDT this evening FOR KSZ008-020-021-
034-035.

&&

$$

SHORT TERM...Wolters
LONG TERM...65
AVIATION...Wolters
FIRE WEATHER...Wolters





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