-- Discussion containing changed information from previous version are highlighted. --
498
FXUS64 KAMA 202358
AFDAMA

Area Forecast Discussion
National Weather Service Amarillo TX
658 PM CDT Mon May 20 2024

...New AVIATION...

.SHORT TERM ...
(This evening through Tuesday night)
Issued at 314 PM CDT Mon May 20 2024

The ridge in the jet stream trough continues over our area
through the front half of short term period. A surface low exits
our northern zones this afternoon, and another low is expected to
form in the low to mid levels of the atmosphere by tomorrow. This
low pressure system develops ahead of a trough in the west, and
the next upper level pattern change will unfold upon our area by
Wednesday.

Above average temperatures across the CWA continue to be the main
message today. New 12Z NBM values were adjusted slightly to line
up better with surface observations, 12Z 850 mb temperatures, and
incoming upper level cloud coverage. Generally speaking, most
places today will reside in the mid to upper 90`s, while a few
locations could see 100 degrees or greater in the Canadian River
Valley, Palo Duro Canyon, and the far south eastern Texas
Panhandle. While temperatures in the Canyon do not meet criteria
for a Heat Advisory, those who have to be outside in those parts
are advised to be cautious. Palo Duro is still forecast to reach
103 degrees this afternoon.

Tuesday, slightly cooler temperatures are forecast area wide as a
surface trough ejects into our area from the west and breezier
winds are anticipated with it. With 850 mb temperatures dropping
around 26 degrees Celsius for the Panhandles, an array of upper
80`s and lower 90`s are in the forecast. Only minor changes were
made from the NBM temperatures.

Rangel

&&

.LONG TERM ...
(Wednesday through next Sunday)
Issued at 314 PM CDT Mon May 20 2024

An upper level trough moves into the High Plains at the start of
the extended period. Once this system moves through, the upper
level pattern returns to more zonal flow. 500 mb heights will rise
slowly through the rest of the week, but a ridge in the jet stream
trough is not expected to fully develop over our area at this
time.

Wednesday will see surface temperatures return to average values
for this time of year thanks to a cold front that will have moved
through the whole CWA by the morning hours. Winds will be
light to breezy from the north, and partly cloudy skies will
settle in. Eventually towards the overnight hours, surface winds
will veer to the southeast and remain that way until Thursday
afternoon. On Thursday, warm air advection from the south will
allow for moisture to return to the area. However, a dryline is
expected to set up during the afternoon. So areas that end up west
of the trough will experience drier air and southwesterly winds.
12Z NBM guidance and LREF probabilities suggest there is still a
50-70% chance the dryline holds in eastern two stacks of counties
in the Panhandles (Beaver to Donley and eastward). Meanwhile the
probabilities sharply decrease any further west; (only a 10% for
the dryline to hold in Amarillo). Thunderstorms are possible once
again ahead of the dryline, but confidence is not high enough to
increase PoPs beyond their chance probabilities in our area.
After all, there`s still a 30-50% chance the dryline stays well
east of our CWA. The primary hazards at this point will likely be
large hail and damaging winds.

Friday onward, 90 degree temperatures return for the Panhandles
and benign weather conditions are anticipated. Current long range
guidance does not have us reaching the 100`s again, since the
progged upper level pattern won`t support it at this time. We will
still monitor for changes as those days get closer.

Rangel

&&

.AVIATION...
-- Changed Discussion --
(00Z TAFS)
Issued at 645 PM CDT Mon May 20 2024

For the 00Z TAFs, a period of low level wind shear is expected to
develop at the terminal sites from about 07Z tonight until around
14Z Tuesday. Gusty west to west northwest winds are then anticipated
mid morning Tuesday into at least part of the afternoon hours. No
precipitation is foreseen through late Tuesday afternoon.

02
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX                62  90  52  81 /   0   0   0   0
Beaver OK                  61  89  51  82 /   0   0   0   0
Boise City OK              56  84  46  78 /   0  10   0   0
Borger TX                  64  93  54  84 /   0   0   0   0
Boys Ranch TX              61  90  52  84 /   0   0   0   0
Canyon TX                  60  89  52  82 /   0   0   0   0
Clarendon TX               63  90  55  80 /   0   0   0   0
Dalhart TX                 54  86  47  80 /   0   0   0   0
Guymon OK                  58  87  49  80 /   0   0   0   0
Hereford TX                60  90  51  83 /   0   0   0   0
Lipscomb TX                64  91  54  81 /   0   0   0   0
Pampa TX                   64  89  53  80 /   0   0   0   0
Shamrock TX                64  92  56  81 /   0   0   0  10
Wellington TX              65  94  57  83 /   0   0   0  10

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...None.
OK...None.
&&

$$

SHORT TERM...55
LONG TERM....55
AVIATION...02