Drought in Nebraska, September 20 to 30, 2022

AREA FORECAST DISCUSSION
National Weather Service Hastings NE
734 PM CDT Mon Sep 19 2022

...Aviation and Climate Update...

.DISCUSSION...(This evening through Monday)
Issued at 311 PM CDT Mon Sep 19 2022

Rest of Today into Tonight...
Near record to record high temperatures are expected this
afternoon across the area. Grand Island already hit the record
high for today of 97 between 3 and 4 PM. It will be a close call
for Hastings on if we can reach that record over the next hour or
two before we start to cool off this evening. Lows tonight will
also remain warm with a light southwesterly breeze and we will
again be within a few degrees of setting the record warm minimum
temperature for September 20th. Our low Tuesday morning should be
around 67-68 degrees and the record warm minimum for Tuesday is
70, so if we end up just a bit warmer and don't cool below 70
tonight then we can break that record.

Tuesday...
This will be a very unpleasantly hot day with just a light
southwest wind ahead of the cold front for most areas and near
record to record highs in the upper 90s (Neb) to just over 100
(Kansas). The big upper level ridge over the Southern and Central
Plains will be responsible for this heat for one last day. The
cold front will work its way south Tuesday evening and we have
introduced a slight chance for thunderstorms along this front
during the late afternoon and primarily evening hours. Based on
the expected location of the cold front Tuesday evening, the best
chance for thunderstorms will likely run from around York to
Hastings and then slide southeast, but again this is still just a
slight chance. Both the instability and wind shear will be fairly
marginal but can not rule out a few strong to marginally severe
thunderstorms should storms develop.

Tuesday night...
The cold front will continue to slide south and the entire area
will be behind the cold front with cooler air moving in. A
vort max will round the top of the upper ridge and move into the
region from the west helping to enhance our chances for post
frontal precipitation late Tuesday night. The only threat for
isolated strong to severe thunderstorms will be along the cold
front Tuesday evening. Anything that develops well behind the
front late Tuesday night should be non-severe.

Wednesday through Thursday...
The big stories will be the much cooler weather and the increasing
chances for rain.

High temperatures on Wednesday behind the cold front will be in
the 60s across most of our Nebraska counties to the 70s over our
Kansas counties. Even cooler weather is expected for Thursday with
highs only in the mid to upper 50s for most of our forecast area
with plenty of clouds.

Our best chances for rain with this set up will run from Wednesday
through Wednesday night, but could linger into Thursday,
primarily Thursday morning. Severe weather is not expected and
these will primarily be showers or perhaps just a few weak general
thunderstorms. Many areas could see 0.25 to 0.75 inches of
rainfall.

Thursday Night into Friday...
A shortwave will track from west to east across the region and
bring another uptick in our rain chances. Best chances for rain
with this shortwave will be late Thursday night into Friday
morning. This should just be rain, am not even calling for
thunderstorms at this point in time. Temperatures will begin to
moderate back into the 70s by Friday.

Saturday through Monday...
We'll start off with a zonal upper level flow pattern and
transition into northwesterly flow as an upper ridge builds across
the western United States. Overall, this feels like a fairly
normal seasonal pattern with highs in the 70s to maybe around 80
and likely dry conditions.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Wednesday)
Issued at 730 PM CDT Mon Sep 19 2022

- General overview:
High confidence in VFR ceiling/visibility, with only limited
passing mid-high level clouds mainly above 10K ft. High confidence
in dry/thunderstorm-free weather through the vast majority of the
period, although the final few hours bring a few question marks
(see below). Surface winds not a major concern with sustained
speeds mainly near-to-below 10KT throughout, but there is some
directional uncertainty late in the period. A round of modestly-
strong low level wind shear (LLWS) is likely overnight.

- Outside chance of thunderstorms very late in the period?:
Although current TAFs reflect a dry forecast, there is a small
chance (generally 10-15 percent) of high-based shower/weak
thunderstorm development in the general area of both KGRI/KEAR
late Tuesday afternoon (mainly 22-00Z). Given such a low
probability of occurrence and also given this is so far out in
this valid period, will opt against TAF inclusion.

- Wind details:
- Surface winds:
No major issues expected here, as sustained speeds throughout
should average near-to-below 10KT. High confidence in direction
generally averaging southerly (between southeasterly and
southwesterly) most of the time, but late Tuesday afternoon
(especially after 21Z) an approaching cold front will result in
some directional uncertainty and possible variability. Instead of
trying to specify a particular direction for a time frame so late
in the valid period, will simply run with a variable (VRB06KT)
group for now.

- Low level wind shear (LLWS):
Previous TAFS already featured a LLWS group for KGRI but this
latest issuance has introduced to KEAR as well. Official LLWS
inclusion now runs 05-11Z, as shear magnitude between the surface
and roughly 1K ft. AGL is expected to reach 30-35KT as winds at
this level accelerate to around 40KT from the southwest.

&&

.CLIMATE...
Issued at 730 PM CDT Mon Sep 19 2022

-- Record Temperatures Possible Tuesday, Sep. 20th

Record HIGH Temperatures and forecast for September 20th:
Grand Island......95 in 1920...current forecast 97
Hastings..........96 in 1940...current forecast 96

Record WARM LOW Temperatures and forecast for September 20th
Grand Island......70 in 2019/1970...current forecast 67
Hastings..........70 in 2019/1941...current forecast 68

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

DISCUSSION...Wesely
AVIATION...Pfannkuch
CLIMATE...Pfannkuch

Hazardous Weather Outlook...UPDATED
National Weather Service Hastings NE
951 PM CDT Mon Sep 19 2022

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-
201200-
Phillips-Smith-Jewell-Rooks-Osborne-Mitchell-Valley-Greeley-Nance-
Sherman-Howard-Merrick-Polk-Dawson-Buffalo-Hall-Hamilton-York-
Gosper-Phelps-Kearney-Adams-Clay-Fillmore-Furnas-Harlan-Franklin-
Webster-Nuckolls-Thayer-
951 PM CDT Mon Sep 19 2022

This Hazardous Weather Outlook is for south central Nebraska and
portions of north central Kansas.

.DAY ONE...Overnight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

On Tuesday afternoon, high heat index values of 100 degrees or
slightly higher are expected, mainly within much of north central
Kansas. Along with the heat, parts of north central Kansas could
also see a few hours of near-critical fire weather conditions, due
to the combination of relative humidity as low as around 25
percent, and south-southwesterly winds gusting at least 20 to 25
MPH.

Also late Tuesday afternoon into Tuesday night, there is a chance
for showers and a few thunderstorms across various parts of the
outlook area, including the possibility for a few strong
thunderstorms mainly before midnight. Chances for showers and
weaker thunderstorms will then persist through Wednesday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

&&

More information may be obtained at the following web page:
   https://www.weather.gov/hastings

Pfannkuch