Storm Prediction Center Day 1 Fire Weather Outlook
Created: Sun Mar 4 07:29:02 UTC 2018 (
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Storm Prediction Center Day 1 Fire Weather Outlook
Created: Sun Mar 4 07:29:02 UTC 2018 (
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Click for Day 1 FireWX Areal Outline Product
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 040727
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0127 AM CST Sun Mar 04 2018
Valid 041200Z - 051200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PARTS OF EASTERN NEW
MEXICO...THE TEXAS/OKLAHOMA PANHANDLES...AND FAR SOUTHEASTERN
COLORADO...
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN AND
CENTRAL HIGH PLAINS...
...Synopsis...
A compact belt of 80-90 knot mid-level winds -- near the base of a
large-scale western U.S. trough -- will move eastward over the four
corners region and emerge over the plains through tonight. As this
occurs, a lee cyclone over eastern Colorado is expected to rapidly
deepen to ~996 mb while shifting toward western Kansas/Nebraska by
evening. An associated dryline will extend southward from the
surface cyclone -- initially being located along a N/S line near the
Colorado/Kansas and Texas/New Mexico borders this morning before
surging eastward into western Nebraska, western Kansas, most of the
Oklahoma/Texas Panhandles, and western portions of the Edwards
Plateau into this evening. A cold front is then forecast to shift
across much of the central and southern High Plains tonight.
...Dangerous fire-weather conditions expected across parts of the
central and southern Plains...
A large area of high-end Critical fire weather conditions are
expected today as strong low-level winds interact with an
antecedently dry air mass and fuels that remain very dry from recent
drought conditions.
Downslope low-level westerly flow is forecast to strengthen today as
the surface pressure gradient associated with the aforementioned lee
cyclone tightens and efficient deep-layer mixing transfers
higher-momentum air from aloft (from the approaching speed maxima)
to the surface. Poor overnight RH recoveries, resulting from a very
dry air mass, suggest that Critical fire weather conditions may
already be ongoing to the west of the dryline this morning. Fire
weather conditions are then expected to intensify while spreading
eastward with the dryline surge through the day. The precise eastern
edge of the Critical fire weather area is somewhat uncertain, as it
will be modulated by how far east the dryline progresses --
something which model guidance often struggles with. Critical to
high-end Critical conditions are expected west of the dryline, with
sustained wind speeds of 20-30 mph (higher gusts), RH values of
5-15%, and very dry fuels.
An Extremely Critical fire weather area has been maintained across
portions of northeast New Mexico, far southeastern Colorado, and far
southwestern Kansas where RH values of less than 10%, sustained wind
speeds in excess of 30 mph (with gusts in excess of 50 mph), the
center of the thermal ridge, and ERC values into the 90th percentile
intersect. The Extremely Critical fire weather area was expanded
slightly farther southwest into central New Mexico based on the
latest high-resolution guidance.
A pacific cold front is expected to cross through the area from west
to east overnight. While cooler temperatures are expected in its
wake, the air mass behind it will be extremely dry and may allow
Elevated/Critical conditions to persist into the overnight as
sustained winds remain 20+ mph behind the front (especially across
eastern Colorado, western Nebraska/Kansas, and the Oklahoma/Texas
Panhandles). Additionally, the abrupt wind shift -- to northwesterly
-- associated with front will likely exacerbate any ongoing fire
fighting efforts.
...Portions of Florida...
00Z soundings at TBW/TLH depict a very dry air mass across much of
Florida -- except near the Atlantic Coast. This air mass is expected
to remain in place today, as post-frontal northeasterly flow
persists. While critical RH values (i.e., less than 35%) are
expected across the area and fuels are relatively dry, sustained
surface winds are forecast to remain around 10-15 mph, which
supports Elevated fire weather conditions. A Critical fire weather
area could be needed in a future update if trends in guidance
suggest sustained winds speeds will be stronger than currently
forecast.
...Portions of Georgia and South Carolina...
While a dry air mass -- with critically-lowered RH values -- is
forecast over the area, the lack of stronger low-level flow (e.g.,
sustained surface winds are forecast to generally remain less than
10 mph) precludes introduction of an Elevated area. However, locally
Elevated fire weather conditions are possible where wind speeds are
enhanced and fuels receptive.
..Elliott.. 03/04/2018
...Please see www.spc.noaa.gov/fire for graphic product...