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Area forecast discussion...updated 
National Weather Service Norman OK
617 PM CDT Fri Oct 28 2016

Aviation...29/00z taf issuance...
VFR conditions will prevail through the period. The primary
concern for aviation will be increasing southwest winds midway
through the period, Saturday morning into the afternoon. Western
taf sites will see winds remain elevated overnight, sustained 10
to 15 kts gusting to around 20 to 25 knots at times, out of the
south and southwest. Through noon Saturday, gusts will approach 30
knots with sustained winds between 15 and 25 knots possible. No
significant wind shifts are expected.



Previous discussion... /issued 246 PM CDT Fri Oct 28 2016/

the synoptic scale pattern features strongest westerlies aloft
extending from California northeastward across the northern
rockies and northern plains and into New England. Weak flow and
mean ridging is present across the Southern Plains extending into
the southeast. Our area is on the western edge of a surface high
where gradient has tightened between this high and deepening
surface trough in the Lee of The Rockies. This has resulted in
south-southwesterly winds increasing today, particularly across
western Oklahoma where sustained speeds have been observed around
or just above 20 knots.

One shortwave trough now located over California will pass to our
north this weekend forcing a cold front into Oklahoma on Sunday.
This may lead to a fairly substantial temperature gradient from
north to south as the front stalls and becomes diffuse, but this
may be dependent on how much Post-frontal stratus exists. At this
time it appears that stratus may not be very extensive and should
diminish during the morning as the front weakens and low level
flow turns southeasterly in response to the next shortwave
crossing The Rockies and attendant surface pressure falls that

This next shortwave should pass far enough to our north to have
little impact to our weather. Breezy southwest winds should
continue into Tuesday. Uncertainty grows from mid week into late
week as a complicated upper flow pattern evolves and time range
means that the typical spread in ensemble members and differences
among deterministic guidance are seen. Confidence on precipitation
for any one period was not very high, but the fast moving
shortwave diving southeast just east of US may force a cold front
through Wednesday evening which could result in some showers and
thunderstorms then. Chances could possibly linger early Thursday
in the southeast if the slower frontal passage depicted by the
European model (ecmwf) (12z run) is seen. Confidence in this period is below


Fire weather...
the combination of winds and relative humidity values this
afternoon, tomorrow afternoon and again Monday afternoon leads to
some fire weather concern. Magnitude appears to be sub-critical,
with only elevated or near critical conditions expected all three
of these days. Recent relative humidity recovery at night because of a
persistent moist air mass and occasional morning dew/fog has been
sufficient to keep erc values near or only slightly above normal.

This afternoon: we are nearing peak mixing as of this writing and
relative humidity values at gage, Woodward and Alva range from around 25 percent
to around 30 percent. Sustained 20 foot wind speeds are 20 to 25
mph. Critical thresholds may briefly be approached through late

Saturday: the 20 percent or below minimum relative humidity values should be
across portions of Woods, Woodward, Ellis and Harper counties, and
this may be misaligned with the band of strongest 20 foot winds
from north-central Oklahoma into southwest Oklahoma where surface
pressure gradient is tightest.

Sunday: a cold front should bring cooler and more moist air mass
into at least northern Oklahoma precluding fire weather concerns.

Monday: relative humidity may fall to near critical thresholds again in the
northwest. 15 to 20 mph sustained winds will be present, but the
tightest gradient and highest speeds may again be misaligned with
the lowest relative humidity values.

Tuesday: slightly cooler temperatures are anticipated and this
should keep minimum relative humidity values at or above 30 percent.

near record high temperatures are possible the next few days. Here
are the records for Oklahoma City and Wichita Falls today through
next Thursday.

Oklahoma City

October 28...89 set in 1938
October 29...89 set in 1950
October 30...87 set in 1937
October 31...86 set in 1938
November 1...83 set in 1916
November 2...84 set in 2012
November 3...84 set in 1909

Wichita Falls

October 28...92 set in 1938
October 29...92 set in 1937
October 30...91 set in 2003
October 31...92 set in 1934
November 1...87 set in 2012
November 2...87 set in 2012
November 3...86 set in 2005


Preliminary point temps/pops...
Oklahoma City OK 61 84 59 80 / 0 0 0 0
Hobart OK 61 85 57 81 / 0 0 0 0
Wichita Falls Texas 62 86 61 86 / 0 0 0 0
gage OK 61 91 49 76 / 0 0 0 0
Ponca City OK 64 85 56 75 / 0 0 0 0
Durant OK 59 84 63 86 / 0 0 0 0


Oun watches/warnings/advisories...



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