230
FXUS63 KGID 300545
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
1245 AM CDT Mon Sep 30 2024

.KEY MESSAGES...

- Fire Weather concerns starting Monday with Red Flag Warnings
 in place for much of our central, north and west sections of
 the area including the Tri-Cities between 12PM-9PM. Near
 critical weather conditions are expected outside of warning
 areas.

- Winds Monday 15 to 25 MPH and gusting as high as 35 MPH from the
north will be possible behind the passage of a cold front moving
from the NW to SE between 11AM and 7PM. Relative humidity as low as
15-25%.

- This front will briefly drop temperatures Tuesday down to the
upper 60s to lower 70s.

- The end of the week to the start of the next will be dry (<15%
  PoPs) and warm (5 to 15 degrees above average) with occasional
  chances for more fire weather concerns.

&&

.DISCUSSION...
Issued at 300 PM CDT Sun Sep 29 2024

Tonight...

A positively tilted mid to upper level ridge aloft this evening will
allow the dry and clear conditions to carry on overnight as highs
peak in the upper 80s to low 90s. Lows will fall into the low to mid
50s, with low lying areas closer to the upper 40s. Winds will remain
calm to light and out of the south. The erosion of the eastern CONUS
cutoff low, blocking flow over the area for the last few days, will
allow a southern Saskatchewan centered low pressure center to drop a
cold front down south. This cold front will make its way down into
the northern and eventually Central Plains overnight and through the
day Monday.

Monday...

An upper level trough, guiding and strengthening the Canadian based
low, will dip into the Northern Plains Monday establishing NW flow
aloft. The surface cold front will reach the outskirts of our
northwest counties around 11AM, turning the southerly winds north
and cranking them up to 15 to 25 MPH with gusts as high as 35 MPH.
This front will work its way down from the NW to SE through the
evening. Highs will range from the upper 70s to low 90s, coolest to
the NW where the front is able to pass over first.

The combination of gusty winds (>25 MPH) and very dry continental
air behind the front (RH < 20%) will bring Fire Weather concerns to
the NW portions of the area including the Tri-Cities. Red Flag
Warnings will be in place for most of our western and central
Nebraska counties including counties north and west of a line
between Franklin and Hamilton counties.

Tuesday and Wednesday...

Monday overnight lows may fall as low as the low 40s for the NW
areas as a cold air advection pattern is established behind the
front. Cooler temperatures all around will keep Tuesday as the
likely coolest day of the week with highs forecast to top off around
the upper 60s to low 70s. A few to scattered clouds may form through
midweek as low level cold air flows over a diurnal warming surface,
causing some weak instability.

Building high pressure Tuesday will cutoff the northerly flow for
Wednesday as the winds will turn towards the southeast Tuesday
evening through the first part of Wednesday, turning more towards
the SSW in the afternoon. The continuation of dry regional
conditions (15-25% RH) with winds gusts as high as 25 MPH may bring
back spots of near critical fire weather conditions for Wednesday.

Thursday and beyond...

Temperatures will be expected to seesaw between the upper 70s and
upper 80s with dry conditions forecast through the rest of the week.
The extended dry period,  mainly from meridional flow and sinking
air under the cyclonic shear side of the jet, with intermediate
bursts of both light to moderate gusty wind periods could
occasionally bring back the mentioning of fire weather concerns,
especially with the abundance of dry fuel for quick wildfire spread.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1225 AM CDT Mon Sep 30 2024

For KGRI/KEAR Airports:

Prevailing VFR conditions through the period with marginal LLWS
towards morning and a shift in winds with a cold front being the
main focus this TAF period.

For tonight...very marginal LLWS is anticipated to develop as
the LLJ increases ahead of an approaching cold front. Models
indicate winds could increase to near 40KTS by 30/12Z...but with
sustained surface winds near 10KTS+, opted to not mention the
possibility of LLWS in either TAF.

The focus will then shift to a rapidly approaching cold front
which is just approaching the Black Hills region early this
morning. Expect this front to race towards the local are by
mid-morning, eventually reaching north central Kansas by late
afternoon or early evening.

Both the HRRR/NAMnest are indicating wind gusts will approach
30 KTS by midday, and likely not subside until very late
afternoon or early evening as the front pushes well south of the
terminals and surface winds decouple from the stronger winds
aloft as the sun angle decrease late in the day. Timing of this
front is right around noon...with the local passage between
30/16-30/18Z at both terminals when winds will abruptly turn
northerly.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...Red Flag Warning from noon today to 9 PM CDT this evening for
     NEZ039>041-046>048-060>063-072>075-082>084.
KS...None.

&&

$$

DISCUSSION...Stump
AVIATION...Rossi