113 
FXUS63 KTOP 182058
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
258 PM CST Mon Nov 18 2019

.SHORT TERM...(This evening through Tuesday)
Issued at 258 PM CST Mon Nov 18 2019

Recent water vapor imagery showing northwest flow from the 
Pacific Northwest into the southeast states with a few stronger 
perturbations/PV anomalies making their way across the Missouri 
Valley. Above-normal precipitable water values were noted on 
nearly all 12Z central and northern Plains soundings with much of 
saturation in the mid and upper layers and this combined with mid-
level lapse rates near 6.5 C/km were allowing for some areas of 
scattered precipitation to pass through, though only trace amounts
were reported. Deep mixing in the wake of the modified front, 
located in far eastern Kansas early this afternoon, was bringing 
temperatures up to around 70 F in much of central and western 
Kansas, with gusts around 40 mph in central Nebraska. 

Upper ridging builds east into the Rockies tonight, with the
stronger northwest flow shifting away. Clearing skies early this
evening should allow for a decent inversion to develop and keep
the gusty winds to the northwest from impacting the local area.
The stronger winds above the boundary layer should mitigate
anything more than isolated steam fog formation in locations 
protected from west to northwest winds late tonight into early 
Tuesday morning. Another warm day is on tap for Tuesday despite 
modest winds in the 1012 mb surface ridge with only some temporary
bands of mid and high clouds passing. 

.LONG TERM...(Tuesday night through Monday)
Issued at 258 PM CST Mon Nov 18 2019

A moderate south-southwest low-level jet develops Tuesday night
under briefly zonal cross-Rockies flow as multiple upper waves 
enter the southwestern states. With some increase in cirrus 
likely, low temperatures should only fall in the 40s. After a 
brief fall in levels tonight and Tuesday, PW values ramp up to 
near-record levels late Wednesday into Wednesday night as the 
first upper wave quickly moves northeast. Light to at most 
moderate rainfall amounts are likely however given the quick 
nature of this wave. There continues to be indications of lapse 
rates returning to near 7 C/km in the moisture for some elevated 
convective potential for the afternoon and night. Cold air 
advection behind the associated front is again modest and even the
coldest solutions keep temperatures above freezing and prevent a  
wintry precip concern from materializing. 

The evolution of the second wave remains very uncertain as it
attempts to cut off from the split flow. The 12Z GFS and most of
its ensembles along with the 12Z ECMWF are much weaker and faster
with the wave, however some light precipitation remains possible 
with the weakening wave Friday and Friday night, with continued 
CAA allowing for some various precip types. Overall the confluent
pattern does not favor anything more than a modest winter event.

Split flow continues through the weekend into early next week with
moderating temperatures on tap. There is fairly good agreement in
a shortwave digging into the central Rockies just beyond this
forecast however. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1140 AM CST Mon Nov 18 2019

VFR conditions should continue. Modest, scattered, high-based 
showers will move through the area over the next few hours with
little surface impact. Some gusts may yet develop around 21Z for a
few hours (primarily MHK) as mixing depths increase behind a 
surface trough. There is some minor potential for low-level wind 
shear around 03Z as surface winds decouple but any shear looks too
weak and brief for inclusion.

&&

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

$$

SHORT TERM...65
LONG TERM...65
AVIATION...65