Area Forecast Discussion
Issued by NWS Amarillo, TX

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS64 KAMA 111122
AFDAMA

Area Forecast Discussion
National Weather Service Amarillo TX
622 AM CDT Sun Apr 11 2021

.AVIATION...12Z TAFs...

Primary aviation concern is the arrival of a cold front this
evening, which will likely bring some at least 25 to 35 knot
northeasterly gusts to all sites. In the interim, expect initial
westerly winds to become northwesterly at all sites before the
front arrives. Exception is DHT, where wind direction remains
uncertain due to the presence of a surface trough this morning and
the potential for an enhanced easterly component as the western
extent of the front may race ahead just to the east of the Sangre
de Cristos. Otherwise, LLWS at AMA should be tapering off over the
next hour as surface winds begin to tick up a bit following
sunrise.

Ferguson

&&

.PREV DISCUSSION... /Issued 329 AM CDT Sun Apr 11 2021/

SHORT TERM...

08z WV satellite reveals an upper low over CMI, a northern stream
wave over MT, and quasi-zonal west-northwesterly flow aloft over
the Panhandles. At the surface, a cold front associated with the
MT wave is beginning to push south through SE WY and the NE
Panhandle.

For Sunday, expect a quick warm up as the lee surface trough shifts
eastward and winds gain a dominant downslope westerly component.
These dry conditions may lead to a resumption of elevated fire
weather concerns, as discussed below.

Sunday evening into the overnight hours, the aforementioned cold
front will push south through the forecast area. Given progged
surface pressure rises, 35-45 knot winds seen at 850mb, and the fact
that our most recent cold front seemed to vastly overachieve despite
weaker pressure rises and 850mb winds, have gone toward the high end
of guidance sustained winds and gusts between 10pm and 4am. Do think
the nighttime arrival should keep things from getting into high wind
territory, but this will need to be watched closely.

Monday, surface high sets up over the central Plains, leading to
easterly winds in the Panhandles. Thus, given these upslope winds,
expect the first of several days with below average temperatures.

Ferguson

FIRE WEATHER...

Elevated fire weather conditions are expected as a lee surface
trough shifts eastward early this morning, leading to efficient
warming and drying at the surface via downslope winds out of the
west. With RH values dropping into the 7 to 13 percent range and 20
foot winds, initially out of the west at 10 to 15 mph shifting to
out of the north and the northeast at 15 to 25 mph late this
afternoon into this evening, do think elevated fire conditions will
be possible in the Oklahoma and northern Texas Panhandles.
Composition of the fuels, in a transitional green phase, remains
uncertain.

Ferguson

LONG TERM...
On Tuesday, an upper level ridge is expected to stretch east-west
across central Canada.  On the underside (south) of the ridge there
ie expected to be and east-west oriented trough that extends from
the Pacific Northwest coast to the Great Lakes with 2 cutoff lows,
one over the Pacific Northwest and another over Minnesota. The
Minnesota low will help to supply the Panhandles with cooler air
from Canada and the Pacific Northwest low will have several minor
disturbances that will rotate through the base of the trough and
eastward across the Panhandles.  The Pacific Northwest low will only
slowly move southeast to the northern Great Basin by Tuesday night
where it will hang out until about Friday before it moves out onto
the northern Plains by Friday night.  This will help to drive
another cold front through the Panhandles on Friday, which will help
to make for another cooler day on Saturday with highs generally in
the 50`s.

Now about the rain chances.  Models are not agreeing on the amount of
rainfall for the Panhandles from Tuesday onward.  The GFS is much
wetter and the ECMWF is much drier, but both models are fairly
similar on their upper air pattern.  It appears that the GFS has
much more low level moisture to work with than the ECMWF. Therefore,
the GFS produces more widespread rain and the ECMWF only produces
very isolated showers. The reality will probably fall somewhere in
the middle.

High temperatures from Tuesday on will likely be stuck in the 50`s
and 60`s given the cloud cover and potential rainfall.

&&

.AMA Watches/Warnings/Advisories...
TX...None.
OK...None.

&&

$$

77/15


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.