298 
FXUS63 KTOP 011130
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
530 AM CST Sun Mar 1 2020

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 247 AM CST Sun Mar 1 2020

Early this morning an upper level trough was moving east across 
the northern Plains. Low-level CAA across the northern Plains 
this morning will cause a surface front across southeast SD, 
southwest into western NE to push southeast into the northwest 
counties of the CWA late this afternoon. High and mid level 
cloudiness will increase Today and some models show an area of 
stratus moving northeast across the southeast portions of east 
central KS during the late morning and into the afternoon hours. 
Lower SFC-H5 heights along with more cloud cover will keep highs 
a bit cooler Today across the CWA. Expect the warmest highs to 
reach the mid to upper 60s across northeast and east central KS 
ahead of the surface front. North central KS will see lower to 
mid 60s for highs, and they may be a few degrees cooler if the 
surface front moves southeast into north central KS a bit faster 
than progged.

Tonight, the surface front will move southeast of the CWA during
the evening hours. A low amplitude short-wave trough will dig
southeast across MT into WY and CO. The stronger ascent combined
with upslope flow across the central high Plains will cause snow
to develop through the night. The light snow may spread east
across northwest KS and southwest NE. The CWA should remain dry
with low-level CAA dropping low temperatures into the lower to mid
30s. 

.LONG TERM...(Monday through Saturday)
Issued at 247 AM CST Sun Mar 1 2020

Monday, the weak upper trough will shift southeast across NE and 
northern KS. There may be enough ascent for light snow across north 
central KS but during the morning hours. The stronger ascent will
weaken and shift east of the CWA after 18Z MON. I cannot rule out
a sprinkle or flurry across northeast and east central KS during 
the mid morning hours. North winds will keep highs in the mid 40s 
along the NE border to around 50 degrees across east central KS. 
an upper level trough across central CA will dig southward off the
northwest Mexican coast line.

Monday night through Wednesday night, all the extened range models 
show the upper low across northwest Mexico shifting east-northeast 
across southern TX into the lower MS River Valley. This will keep the 
richer moisture and stronger ascent well south of the CWA. Expect 
dry conditions with high temperatures warming into the mid to upper 
50s on Tuesday and lower to mid 60s on Wednesday. 

Thursday, an upper level trough across western Canada will dig 
southeast across the northern Plains into the mid MS River Valley. 
The stronger ascent will remain north and northeast of the CWA. Weak 
low-level CAA will cause a surface front to move southeast across
the CWA Thursday afternoon. Highs on Thursday will reach the 
lower to mid 60s.

Thursday night through Friday, a surface ridge of high pressure will 
build southeast across eastern KS, then shift east of the CWA late 
in the afternoon. High temperatures will be slightly cooler with 
upper 50s to lower 60s.

Friday night through Sunday, expect a warming trend as an H5 ridge 
moves east across the Plains Saturday and a lee surface trough 
deepens across the High Plains. Southerly winds will help high 
temperatures to warm into the mid to upper 60s both Saturday and 
Sunday. There may be an elevated fire danger on Saturday as deep 
mixing may cause RHs to drop below 30 percent and south winds will 
increase to 15 to 25 MPH with higher gusts. Sunday, there will 
probably be richer gulf moisture advection and RHs will be higher, 
though southerly winds will continue to be gusty.

&&

.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 524 AM CST Sun Mar 1 2020

12z UA sounding at KTOP showed a 50 KT south-southwesterly low-
level jet about 1100 feet above the surface, so I expect the low-
level windshear of 30 to 40 KTS to continue at KTOP and KFOE
through 14Z. Once the boundary layer mixes deep enough there may
be a period of stronger surface winds and wind gusts through the
mid morning hours before winds subside under 11 KTS by 18Z. Most
numerical models show the MVFR stratus developing across eastern
OK, remaining southeast of the KTOP and KFOE terminals. I placed
sct stratus of 3000-3500 feet at 18Z, just in case the few
numerical models that show the western edge of the stratus
reaching KTOP and KFOE this afternoon verifies. A cold front will
switch winds to the northwest at MHK by 20Z and at KFOE and KTOP
by 23Z. If there is any stratus at KTOP and KFOE it will shift
east ahead of the front. 

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Gargan
LONG TERM...Gargan
AVIATION...Gargan