Area Forecast Discussion
Issued by NWS Topeka, KS

Home | Current Version | Previous Version | Text Only | 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 KTOP 212318

National Weather Service Topeka KS
518 PM CST SAT NOV 21 2015


.SHORT TERM...(This Evening through Sunday)
Issued at 200 PM CST SAT NOV 21 2015

Northwest flow prevailed across the central CONUS this afternoon.
A weak disturbance in the flow over western North Dakota per water
vapor imagery should move across the central plains tonight. The
wave should generate some cloudiness across northeast Kansas
tonight before exiting Sunday morning. In the meantime, the
surface ridge was over central Kansas at 19 UTC.The 12 UTC models
push the surface ridge to the south after 06 UTC tonight as
southwest surface flow develops. Warm advection after midnight
along with clouds should keep temperatures up a little. Overnight
lows may actual happen early on.

For Sunday, southwest flow boundary layer flow along with warm
advection prevail. Aloft, northwest flow starts to flatten to
quasi-zonal by Sunday evening. Plenty of sun and warm advection
will allow temperatures to rebound into the upper 40s to lower 50s
Sunday afternoon.

.LONG TERM...(Sunday Night through Saturday)
Issued at 200 PM CST SAT NOV 21 2015

Quasi-zonal flow prevails early in the long range. The 12 UTC
models are decent agreement on Monday and Tuesday with respect to
the large scale features. The upper flow buckles north of a strong
upper jet over the eastern Pacific and the western CONUS. As a
result, a upper low is forecast to move onshore reach the Great
Basin by 12UTC Wednesday. Downstream, the upper air pattern
gradually becomes southwesterly in time.

At the surface, southerly flow continues and eventually low-level
moisture should return into the central plains due to prolonged
southerly flow and eventually an open Gulf of Mexico. For the
sensible weather, mild and dry weather is forecast for Monday and
Tuesday across northeast Kansas.

In the extended...
Thanksgiving Day into early Friday morning are where some low
confidence enters the forecast in the extended period.  The deep
upper level trough and closed low over the Four Corners region will
begin to lift into the Central Rockies and into the Central Plains.
Ahead of the system on Thursday looks to remain warm enough for all
precipitation to be rain with slight chances of thunder with at
least some areas of instability aloft.  The likely scenario will
probably be some good areas of widespread heavy rain.  Into the
evening Thursday night is looking like a potentially interesting
time frame with the arrival of a strong cold front that will usher
in sub-freezing temps.  Just which model will verify is the main
question as to whether a freezing/mixed precip event occurs over
northeast KS or not. If the GFS verifies, then all precip will
have pushed East and when the cold temps arrive there should be
virtually little concern. If the Canadian or ECMWF are more in
line with the outcome, then there is a rather good possibility
that at least a short time frame will set up conducive to seeing
mixed or freezing precip starting early evening over East Central
KS and then working East/southeast as the entire system lift out
of the region. Either way, this will be something to watch and
certainly isn`t set in


.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 518 PM CST SAT NOV 21 2015

Shortwave moving through the back side of the upper trough should
continue bringing mid level clouds across northeast KS. There is a
weak signal of enough forcing for some very light precip
overnight. However this appears to be a very low impact and mainly
north of the terminals. Therefore will maintain a VFR forecast
expecting dry air in low levels to prevent any precip from
reaching the ground.


.TOP Watches/Warnings/Advisories...NONE.



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