Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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

FXUS64 KLUB 170745

Area Forecast Discussion
National Weather Service Lubbock TX
245 AM CDT Tue May 17 2022

With surface winds returning to the south and southwest today, we
expect temperatures to be warmer than Monday with highs ranging
from the upper 90s to near 104. Relatively high dewpoints
(40s-60s) early this morning will drop during the afternoon as the
dryline mixes eastward. We should see elevated fire weather
conditions and plan to issue a Rangeland Fire Danger Statement.

As for rain chances, we will go with a dry forecast, but want to
note that some of the CAMS models including the HRRR show
isolated convection as the dryline mixes east. As typical the
NAMNST is more agressive and shows a line of convection developing
from near Memphis southwest to just SE of Lubbock during the
afternoon. We will lean away from that solution and plan to keep
pops below 15 percent. Any convection that does try to form should
rapidly decrease by early evening as temperatures begin to cool.

No significant changes to the long term forecast package this
morning. A weakening front will move through the region early
Wednesday, stalling in vicinity of the Permian Basin and into the
Concho Valley beneath an increasingly barotropic airmass. High
temperatures will range from the lower 90s across the extreme
southwestern TX PH into the middle-upper 90s throughout the rest of
the South Plains, with triple-digits in the Rolling Plains. Winds
will be light, generally at or less than 10 mph by the afternoon,
precluding any fire weather concerns. Gradient winds will shift to
the southwest while becoming breezy on Thursday as synoptic-scale
flow begins to amplify across the northern Rocky Mountains as a
potent shortwave trough rotates towards the northwestern Missouri
Plateau along the 49th parallel. Intense dry-bulbing is expected
with vertical mixing heights ascending into the mid-levels, with
temperatures breaching 100 degrees across most of the CWA except for
the extreme southwestern TX PH where upper 90s are forecast. Despite
the very-well-mixed boundary-layer, mid- and high-level flow will
still be weak over the CWA, fostering surface winds between 10-20
mph (but enough to make it feel like a blast furnace). The
aforementioned shortwave trough over the Medicine Line/49th parallel
is forecast to phase with a 500 mb closed cyclone over the Hudson
Bay, accentuating the meridional waveguide as a longwave trough
encompasses the central and western two-thirds of the CONUS. A
strong cold front with a cP airmass will invade the CWA on Friday
(therefore tarnishing the once-barotropic state of the airmass),
with a 10-15 deg F to locally 20 deg F temperature gradient forecast
across the CWA. Temperatures will range from the upper 80s to the
lower triple-digits from north-to-south, respectively, with
impressive CAA persisting overnight as lows fall into the lower 40s
and middle 50s by Saturday morning given the strong, northerly
fetch. A welcomed relief temperature-wise is in store this weekend
with highs peaking in the 70s area-wide on Saturday and in the upper
70s to lower 80s on Sunday as surface winds weaken and veer to the
east. There still remains uncertainty with respect to the evolution
of the large-scale pattern by Monday/D7 into D8, as discrepancies
among global NWP guidance exist on potential waveguide amplitude.
However, low PoPs were maintained as ensemble data broad brushes QPF
across the southern Great Plains region and the only change made for
the morning package during this time frame (D7/D8) was to introduce
the mention of severe into the weather grids given the presence of
cross-boundary shear vectors regardless of the amplitude of the mean
flow aloft.



We will cancel the Fire Weather Watch in favor of a Rangeland
Fire Danger Statement for this afternoon and early evening as near
critical fire weather conditions develop. Those conditions are
partially limited by the rains Monday evening as well as increased
mid level cloud cover during the day.




04/09/04 is the U.S. government's official web portal to all federal, state and local government web resources and services.