Area Forecast Discussion Issued by NWS
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000
FXUS64 KLUB 041146
AFDLUB
Area Forecast Discussion
National Weather Service Lubbock TX
546 AM CST Thu Mar 4 2021
.AVIATION...
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Relatively light winds and passing mid-level clouds will be the
rule this morning. However, much stronger westerly winds,
sustained near 25 knots, will overspread the western terminals
this afternoon. The gusty winds will likely kick up some dust
too, though unless winds are higher than expected, restrictions
from BLDU should remain VFR. The winds will decrease to breezy
levels this evening, veering northwesterly late tonight. Further
east, winds won`t be as strong at KCDS today, and will be out of
the south through the afternoon hours before shifting to the west
late this evening. In addition, elevated virga showers will be
possible, especially up toward KCDS, later in the day. These
showers could produce strong sub-cloud downburst and avoidance is
encouraged.-- End Changed Discussion --
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.PREV DISCUSSION... -- Changed Discussion --
/issued 301 AM CST Thu Mar 4 2021/
SHORT TERM...
Today will bring another warm afternoon, though unfortunately it
will come with more wind and a high fire danger, at least for
locations on the Caprock. The culprit providing the wind is a closed
low that is currently churning near Las Vegas early this morning.
The low will continue on an eastward trek across the Four Corners,
emerging over the Oklahoma Panhandle this evening, before shifting
southeastward into central Oklahoma by 12Z Friday. As the low
approaches it will spread stronger winds throughout the depth of the
troposphere out of the Desert Southwest and across the southern High
Plains this afternoon into tonight. In addition, the approaching
system will spur surface cyclogenesis near the collective
NM/TX/OK/CO borders later today, with the surface low translating
eastward, then southeastward, in conjunction with the mid/upper
system. This will open the door for a Pacific cold front and
developing/tightening dryline to spread eastward across the Caprock
this afternoon.
In advance of the front/dryline, mid-level moisture and lift
spreading from southwest-to-northeast could try to squeeze out a few
very high-based elevated showers. Unfortunately, like our last
system, the radar will likely look more impressive than the net
result at the ground, with plenty of echos, but little (if anything)
surfacing before drying up. Mid-level lapse rates will steepen late
in the day as the cold core low draws closer, and this could support
elevated convection near the far northeast corner of the CWA, though
the best chances will be further north and east. This activity
doesn`t hold much hope for any meaningful precipitation, but could
produce erratic and gusty winds and dry lightning. Otherwise,
further west, the main story will be the gusty westerly winds that
will overspread the Caprock this afternoon, generally sustained in
the 20 to 30 mph range, though a few spots could briefly flirt with
low end advisory levels. These strong and dry winds will create
critical fire weather and will also likely loft patchy blowing dust.
On the positive side, temperatures will again top out well into the
70s. Further east, locations off the Caprock will escape the worst
of the winds today.
The wind will decrease modestly this evening (though remain breezy)
as deeper thermally driven mixing ceases. The wind will veer
northwesterly late tonight as the surface low tracks along the Red
River Valley, before even more robust northerly winds invade Friday
morning. Temperatures will fall back into the lower and middle 40s
tonight, with a few 30s across the northwestern and western zones.
LONG TERM...
The aforementioned cold front will be through the area by early
Friday, however, the effects of the front will last for a majority
of the day. With post-frontal pressure rises and mixing to around
800 mb, surface winds over the forecast area will be quite breezy.
With sustained winds of 25 to 35 mph likely much of Friday, the
issuance of a Wind Advisory will be possible. Strong winds will have
the potential to loft dust over the area. As the upper-level low
moves to our east, the boundary layer decouples, and a surface high
moves in from the north late Friday, winds will decrease to below 10
mph, becoming light overnight. An upper-level ridge will replace the
upper-level low on Saturday, bringing calm and dry weather. Surface
winds will become southeasterly as the surface ridge moves off to
the east, promoting warming over the area.
An upper-level short wave trough, embedded within a more expansive
upper ridge, will move over the forecast area on Sunday, tightening
the surface pressure gradient and providing breezy southerly winds.
The area will continue to warm through the weekend and into early
next week as upper-level ridging and southerly surface flow will
remain the main players in our weather.
Our next system will enter the northwestern CONUS next Monday and
start to dig towards the area. Ahead of the main system, a lead
short-wave will bring a cold front through the area mid-week,
decreasing our highs from the 70s on Monday and Tuesday to the 60s
by Thursday. As the main system moves closer late in the week, it
may bring our next chance of precipitation (fingers crossed) Friday
evening into the weekend, or at a minimum increased winds. This is
still over a week out, so a lot will likely change between now and
the event. GKendrick
FIRE WEATHER...
Warm, dry and gusty westerly winds will create critical fire weather
across much of the Caprock this afternoon, immediately behind an
advancing Pacific front and developing/tightening dryline. Westerly
winds sustained at 20 to 30 mph will be common, while highs in the
70s will drive RH values down into the 10-15% range. The combination
of the wind and RH, coupled with rising ERC values (fuels becoming
more favorable to support wildfires) observed in the 75-89%
yesterday, justify the issuance of a Red Flag Warning (RFW). Thus,
we have upgraded the Fire Weather Watch to a RFW for the central and
western South Plains and southwest Texas Panhandle, valid from 11 am
to 7 pm. A shorter period of elevated to critical fire weather will
affect the eastern South Plains and south-central Texas Panhandle
late in the afternoon, and thus we will issue a Fire Danger
Statement (RFD) immediately adjacent to the RFW, valid from 2 pm to
7 pm. Conditions will gradually improve this evening as winds and
temperatures decrease and the humidity increases.-- End Changed Discussion --
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.LUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM this morning to 7 PM CST this
evening for TXZ021>023-027>029-033>035-039>041.
&&
$$
23/10/23