Frost Advisory 4, NWS Topeka, KS

AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1214 PM CDT THU OCT 29 2015

...Update to aviation forecast discussion...

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 233 AM CDT THU OCT 29 2015

Dry air subsidence continues to push southward into northeast Kansas
this morning behind the expansive upper low lifting over Lake
Michigan. Sfc ridge axis noted throughout the central plains has
calmed winds down while quickly cooling temps to lower and middle
30s by sunrise. Made no changes to the current Freeze Warning in
effect through 14Z.

As the modified Canadian airmass settles into the area today, weak
mixing combined with a cold start to the morning results in highs
reaching the mid to upper 50s. For tonight, a mid level trough
deepens over the inter-mountain west, gradually phasing with a
northern stream wave as it pushes eastward towards the CWA Friday.
Increasing high clouds late Thursday evening from the approaching
system may keep lows from falling to the freezing mark in the 34
to 36 degree range. Short term guidance is in decent agreement
with the dewpoints hovering in the mid to upper 20s through
sunrise, lessening the possibility of frost.

.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 233 AM CDT THU OCT 29 2015

The aforementioned upper trough, currently deepening into
southern California, will shift east into Texas by Saturday. Upper
level and mid level southwesterly wind fields will strengthen
substantially Friday into Saturday over the local area, with a
nearly 150 kt upper jet overhead by Friday night. These winds will
transport ample mid/upper level moisture into the region. The low
levels will be quite a bit drier, especially on Friday, but will
see a rapid moistening by late Friday as southerly low level flow
returns. The strong upper jet will provide strong ascent over the
area, especially when combined with deep persistent isentropic
upslope flow and mid level frontogenesis. So, even with the
initially dry low level air, it should saturate fairly quickly by
Friday afternoon and the entire area will see a good chance for
widespread rain showers. Instability is present but very weak so
have not mentioned thunder in the forecast at this time. Total
rainfall amounts should commonly be in the 0.25 to 0.50 range.

The upper forcing wanes by Saturday morning as the system shifts
east but there is a chance for lingering showers (especially in
the morning) as a last wave of mid level frontogenesis is expected
to drift across the forecast area. Current indications point to
dry conditions likely by Saturday afternoon along with decreasing
clouds.

Sunday through Tuesday night are likely to be dry and relatively
warm with a zonal flow pattern overhead and a dry airmass in
place. Highs in the 70s and lows in the 40s should be common. By
late Wednesday into Thursday, another southwestern CONUS trough
remains on schedule to deepen and begin to eject into the Plains.
It currently looks quite similar to the system incoming tomorrow.
Have introduced low end POPs by Wednesday with better chances
looking to come by Friday.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Friday AFTERNOON)
ISSUED AT 1205 PM CDT THU OCT 29 2015

VFR conditions forecast for the entire period at this point. High
confidence in this until the very end of the period. Depending on
how fast this next system develops as it pulls out of the Southern
Rockies will likely at least affect cloud cover for the morning
time frame but CIGS still well above 3kt feet expected. Also, expect
precip to hold off until the afternoon so not adding mention of
that in this forecast.

&&

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

SHORT TERM...Bowen
LONG TERM...Barjenbruch
AVIATION...Drake

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TOPEKA KS
906 AM CDT THU OCT 29 2015

KSZ008>012-020>024-026-034>040-054>056-058-059-301415-
REPUBLIC-WASHINGTON-MARSHALL-NEMAHA-BROWN-CLOUD-CLAY-RILEY-
POTTAWATOMIE-JACKSON-JEFFERSON-OTTAWA-DICKINSON-GEARY-MORRIS-
WABAUNSEE-SHAWNEE-DOUGLAS-LYON-OSAGE-FRANKLIN-COFFEY-ANDERSON-
906 AM CDT THU OCT 29 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL...NORTH
CENTRAL AND NORTHEAST KANSAS.

.DAY ONE...TODAY AND TONIGHT.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THROUGH TONIGHT.

&&

MORE DETAILED INFORMATION CAN BE ACCESSED AT...
HTTP://WWW.WEATHER.GOV/TOP/SITREP