FXUS63 KTOP 300448
Area Forecast Discussion
National Weather Service Topeka KS
1148 PM CDT Sun Mar 29 2020
...Update to aviation forecast discussion...
.SHORT TERM...(This evening through Monday)
Issued at 311 PM CDT Sun Mar 29 2020
A very pleasant afternoon taking place across the area with an
equally pleasant evening and overnight in store.
The potent mid-latitude cyclone that brought very strong winds to
the area and severe weather to the central portions of the CONUS
yesterday as continued it track to the northeast and currently
centered over the Great Lakes region. Quasi-zonal flow remains over
the immediate area with shortwave ridging over the northern Rockies
into the the northern Plains. Another low amplitude trough is
amplifying over the southwestern United States. High pressure and a
downslope flow regime is in place more near the surface across the
forecast area in between the two main weather systems.
As a result of the influence of the downslope flow and fairly high
mixing heights, temperatures across the area have pushed up to the
upper 60s with some 70s across the area near where they should top
out. Mainly dry air is in place with only some shallow saturation
atop the mixed layer where some sparse shallow cumulus have formed
across a portion of northeastern Kansas. Several fires continue to
to burn this afternoon also responsible for the smoke in the air.
However, several of these small fires have been burning themselves
out over the hour or two. There has been an area of very high fire
danger over portions of east central Kansas associated with low
humidity and some of the more brisk winds today as well as slightly
higher temperatures. This will diminish by sunset as winds calm.
Have not made mention of the very high fire danger other than this.
Tonight, good radiational cooling should take place and allow for
lows to drop to around 40 across the area. Slightly lower
temperatures across northern areas are slower to return to the south
as the area is in overall transition of high pressure regimes and
situated in somewhat of a "col" zone.
.LONG TERM...(Monday night through Sunday)
Issued at 311 PM CDT Sun Mar 29 2020
The main weather system of interest for the mid to long range
forecast is the early week system which arrives late Monday into
Monday night across the area. No severe weather is anticipated at
this time, but some thunder may materialize over some areas.
The overall system coming in from the southwestern CONUS is set to
deepen off to the south of the area. All forecast models suggest
the southern track is on course, so the concern this far north will
be how much precipitation we actually realize as soundings do work
in dry air - especially maintaining the near surface dry air up to
around at least 5kft. On top of this, shallow areas of lift within
the saturated layer appear to be likely as the most favorable upper
dynamics translate to the south with the upper PV anomaly. That
said, there is weak mid level isentropic ascent that develops across
the area. Best times appear to be around sunset through the early
morning hours on Tuesday. Due to higher theta-e airmass still to
the south of the area and a mostly neutral tilt to the overall
upper trough, expect low overall precipitation amounts out of this.
There is also a layer of shallow instability during the overnight
time frame, so there could be a few thunderstorms embedded within
mostly light rainshowers. Thus, some areas could pick up an inch of
A few rain and possibly storm chances set up into the latter part of
the week as upper flow sets up over the Rockies and encourages
southerly flow back into the area and moisture return. Difference
in timing with any resulting baroclinic systems that advance into
the area, so have kept only slight to chance POPs for Thursday and
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1143 PM CDT Sun Mar 29 2020
Expect VFR conditions through 00Z TUE. An upper level disturbance
will move east across the Plains and bring an increasing chance of
scattered rain showers through the evening hours. Stratus with VFR
ceilings will develop across the terminals, and if the rain
showers increase in coverage, wet-bulb cooling may drop ceilings
below 3000 feet late Monday evening. There is too much uncertainty
in the chances for rain showers that I did not place in any MVFR
ceilings late Monday evening.
NWS TOP Office Area Forecast Discussion