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000 
FXUS63 KGID 222331
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
631 PM CDT Sun Oct 22 2017

.UPDATE...
Issued at 631 PM CDT Sun Oct 22 2017

Increased cloud cover a bit thru tomorrow to acct for the tufts of
cirrostratus streaming into the CWA. There should also be a few
altocu 9-13K ft around dawn tomorrow followed by a few stratocu
with daytime heating tomorrow afternoon.

&&

.SHORT TERM...(This evening through Monday)
Issued at 240 PM CDT Sun Oct 22 2017

Fire Weather:
The main forecast concern in the short term is fire weather. Winds
are breezier today than originally expected and RH values dropping
to just below 20% this afternoon, do not expect much to change
tomorrow. The 20mph + Winds is not a question, the only question
remains in how low RH values will go. With current forecast RH
values between 18 and 20, have decided to issue a Fire Weather
Watch for portions of Kansas and Nebraska where critical fire
weather values are met. Decided a Watch vs. a Warning to give the
next shift some leeway as some of the details become more fine
tuned. Confidence is fairly high we will meet the below 20% RH and
above 20mph winds for these Watch counties. Elsewhere the RH
values are between 20 and 25%, so near-critical fire danger 
across the whole of south central Nebraska and north central 
Kansas. 

Winds:
A potent disturbance will dive southward tonight with a cold front
moving through early Monday. This front will cause westerly winds
to become northwesterly and be quite gusty. Expected northwest
winds of 25 to 35 mph and gusts to over 40 mph are possible.  

Temperatures:
This cold front is not ushering in much cooler air, with
temperatures tonight expected in the 40s and highs tomorrow in the
60s. Minimal clouds and mixing will help temps reach the 60s
tomorrow.  


.LONG TERM...(Tuesday through Sunday)
Issued at 240 PM CDT Sun Oct 22 2017

Fire Weather:
Tuesday and Wednesday are also days to look out for Fire Weather
concerns. Tuesday has slightly higher RH values, but they are
still between 20 and 30% with Wednesday having values between 20
and 25%. Winds will be the strongest out of the northwest on
Tuesday, so this looks to be the best additional day for Fire
Weather Concerns, but trough mid-week is a period to watch.  

Temperatures:
It is a bit of a roller coaster with high temperatures this week.
The cooler air will infiltrate behind the wave on Monday, with
Tuesday highs in the 50s. Lighter winds with a downslope component
will help temps on Wednesday reach back into the 70s. By Thursday,
a strong upper disturbance will dive southeast across the Northern
Plains. This disturbance will dislodge a cool Canadian airmass and
temperatures will drop. Thursday won't be as cold, but expect the
high to be early in the day ahead of the front. By Friday high
pressure will be building in and highs are expected in the 30s and
40s. A sharp change from the rest of the week. For the weekend,
Saturday continues to look cool, but it'll warm slightly for
Sunday. 

Overnight lows will drop as well. Saturday morning looks to be the
coldest with lows in the mid 20s. This should effectively end the
growing season for the whole of south central Nebraska and north
central Kansas. 

Winds:
As these potent upper disturbances dive southeast over the area,
northwest winds will be strong Tuesday and then again Thursday and
likely Friday. Sustained speeds will be between 25 and 35 mph with
gusts over 40 mph.  

Precipitation Chances:
As mentioned yesterday, the model guidance has trended dry across
the Central Plains through the whole forecast. The small chances
for precipitation have been removed as of this forecast issuance.
This is a potent upper wave, which will induce lift, but there
will be little in the way of moisture to work with and am not
surprised it is dry now. Earlier forecasts mentioned snow, and if
precipitation is put back in, it is definitely cold enough for
snow, but especially with these moisture starved systems
accumulation is not expected.  

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Monday)
Issued at 631 PM CDT Sun Oct 22 2017

Significant Wx: WSHFT with cold frontal passage 08Z-09Z with LLWS.
Strong winds to at least 40 kts Mon.

Tonight: VFR with no clds at or below 10K until 08Z-09Z when some
sct altocu could move in between 9-13K ft with cold frontal
passage. LLWS develops with FROPA. SW winds 7-12 kts will shift to
NW and increase to around 15 kts. Confidence: High

Mon: VFR with sct altocu exiting to the S in the morning then 
FEW-SCT stratocu form around 7K ft in the afternoon. LLWS will 
end by 15Z as strong NW winds increase to 25-32 kts with gusts as 
high as 43 kts at times. Confidence: High

&&

.FIRE WEATHER...
Issued at 240 PM CDT Sun Oct 22 2017

Winds are breezier today than originally expected and RH values 
dropping to just below 20% this afternoon, do not expect much to 
change tomorrow. The 20mph + Winds is not a question, the only 
question remains in how low RH values will go. With current 
forecast RH values between 18 and 20, have decided to issue a Fire
Weather Watch for portions of Kansas and Nebraska where critical 
fire weather values are met. Decided a Watch vs. a Warning to give
the next shift some leeway as some of the details become more 
fine tuned. Confidence is fairly high we will meet the below 20% 
RH and above 20mph winds for these Watch counties. Elsewhere the 
RH values are between 20 and 25%, so near-critical fire danger 
across the whole of south central Nebraska and north central 
Kansas. 

Tuesday and Wednesday are also days to look out for Fire Weather
concerns. Tuesday has slightly higher RH values, but they are
still between 20 and 30% with Wednesday having values between 20
and 25%. Winds will be the strongest out of the northwest on
Tuesday, so this looks to be the best additional day for Fire
Weather Concerns, but trough mid-week is a period to watch.  

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...Fire Weather Watch from Monday afternoon through Monday evening 
     for NEZ072-082-083.

KS...Fire Weather Watch from Monday afternoon through Monday evening 
     for KSZ005-017-018.

&&

$$

UPDATE...Kelley

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