Air Resources Laboratory banner image
Air Resources Laboratory web site National Oceanic and Atmospheric Administration (NOAA)

ok discuss


Office: TSA

FXUS64 KTSA 140524
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
1124 PM CST Wed Dec 13 2017

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR conditions will prevail through the period. Next frontal
boundary is working its way across the Plains with mid-level
cloudiness beginning to build into northern OK. Cloud deck will
encompass northeast OK and northwest AR terminals and may drop south
into KMLC and KFSM. Winds will become northwesterly by morning but
is expected to remain below 12kt.

&&

.PREV DISCUSSION... /Issued 934 PM CST Wed Dec 13 2017/

..UPDATE...

DISCUSSION...
Currently wide range in temps observed across the area as calm
winds ahead of the next frontal boundary have allowed a quick
temp drop. Updated forecast will incorporate observed trends
however temps will rebound once the winds pick up and will not be
too aggressive with lowering overnight mins.

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&

$$


AVIATION.....11



Office: OUN FXUS64 KOUN 140355 AFDOUN Area Forecast Discussion National Weather Service Norman OK 955 PM CST Wed Dec 13 2017 .AVIATION... TAFS 1406/1506... High and mid clouds will develop ahead of a shortwave trough tonight and Thursday, especially across the northern half of Oklahoma. A light to moderate northerly wind will prevail over the next 18-24 hours. && .PREV DISCUSSION... /issued 601 PM CST Wed Dec 13 2017/ AVIATION... TAFS 1400/1424... Variable high clouds will move over Oklahoma and north Texas through the TAF period. A light northerly wind will prevail tonight and will increase in speed on Thursday. PREV DISCUSSION... /issued 252 PM CST Wed Dec 13 2017/ DISCUSSION... Impactful weather over the next several days is centered around fire weather. Although, the weather/fuel environment does not currently seem to support significant fire weather concern (see details in fire weather section below). Otherwise, temperatures will be normal to occasionally above normal for mid-December. One low-medium probability precipitation opportunity will occur for mainly eastern portions of the area Saturday night into Sunday morning. Changes to the previous forecast were minimal. Within northwesterly flow across the middle part of the country, a weak shortwave is passing through. A band of cirrus across northern Oklahoma early this afternoon is coincident with weak ascent associated with this shortwave. This wave has sent a cold front into the area today resulting in an increase in gusty northerly winds as it passes. There have been a few reports from northwest Oklahoma of some smoke and this doesn't appear to be due to any local wildfire activity, rather MODIS satellite suggests it is probably from the Legion Lake fire in the Black Hills of South Dakota. A more intense shortwave trough will move through tomorrow forcing a more significant cold surge into the area early in the day. High temperatures are expected to be around 15 degrees colder. Latest model runs show a persistent trough in the east and diminishing Rex Block pattern with slowly deamplifying ridge in the west through the end of the week. This will support a continuation of dry northwesterly flow aloft across our region. Notable changes on the synoptic scale occur by Saturday. A closed low, now over northern Baja California, will open up and eject northeastward in response to deepening longwave trough in the west. Despite PWAT values being significantly below normal now across Texas into the western Gulf, modest moisture return will occur quickly in response to this lead shortwave and should be enough for some showers across roughly the eastern two-thirds of the area Saturday night through early Sunday. Instability will be very weak at best, possibly supporting a few weak thunderstorms as well. Eastward progression of this longwave is where uncertainties arise. Deterministic guidance is as much as 24 hours out of phase. Generally, ECMWF and its ensemble mean are much quicker than the GFS and most of its ensembles. If the GFS/GEFS is right, this could offer another low probability precipitation event for the eastern portions of the area sometime around Monday, but we have kept the forecast dry for now given significant uncertainty. BRB FIRE WEATHER... Some fire activity will remain possible through this afternoon. Latest Oklahoma mesonet observations show relative humidity values around or below 20 percent for most of the area, and around 10-15 mph northerly winds behind the southward moving cold front. This is resulting in elevated to near critical fire weather conditions. As mentioned above, a smoke smell may occur behind the cold front moving through the state now. This smoke seems to be originating from the Legion Lake fire in the Black Hills. Latest shortwave band satellite imagery reveals one hotspot and probable fire in western Love County. Local media reports and KTLX radar indicate a minor fire in south OKC. No other ongoing activity is known at this time, but additional initial attack activity is certainly possible through the afternoon. Cooler temperatures and comparatively higher relative humidity should limit fire concerns tomorrow, and although humidity will be lower Friday, winds should remain fairly light. The next fire weather day is expected to be Saturday when gusty southerly winds begin before a surge of low level moisture arrives. Elevated fire weather conditions may result. Latest ERC-G values in western Oklahoma where near or slightly above the 90th percentile which would tend to enhance fire activity even if only marginal meteorological conditions are realized. BRB && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 35 47 30 51 / 0 0 0 0 Hobart OK 33 50 27 54 / 0 0 0 0 Wichita Falls TX 34 53 31 54 / 0 0 0 0 Gage OK 29 49 23 56 / 0 0 0 0 Ponca City OK 32 47 28 51 / 0 0 10 0 Durant OK 36 53 34 54 / 0 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$
Office: AMA FXUS64 KAMA 140547 AAB AFDAMA Area Forecast Discussion...UPDATED National Weather Service Amarillo TX 1147 PM CST Wed Dec 13 2017 .AVIATION... For the 06Z TAFs, a minor upper level low pressure system will move across the area Thursday accompanied by an increase in mid and high level clouds. A few snow flurries or light snow showers may also develop Thursday morning across the northwest sections of the OK and TX Panhandles with KGUY and KDHT possibly being impacted. However, the probability of this happening is low, and have omitted from this fcst cycle. Andrade && .PREV DISCUSSION... /Issued 548 PM CST Wed Dec 13 2017/ AVIATION... For the 00Z TAFs, a minor upper level low pressure system will move across the area late tonight and Thursday accompanied by an increase in mid and high level clouds. A few snow flurries or light snow showers may also develop Thursday morning across the northwest sections of the OK and TX Panhandles with KGUY and KDHT possibly being impacted. However, the probability of this happening is low, and have omitted from this fcst cycle. Andrade PREV DISCUSSION... /Issued 235 PM CST Wed Dec 13 2017/ DISCUSSION... No significant changes have been made to the forecast. Main day of concern will be Saturday, when elevated to critical fire weather conditions are expected. See below. Post-frontal surface high pressure ridge builds into the Texas and Oklahoma Panhandles tonight, with clouds also increasing from the north. Low pops for light snow Thursday morning have been retained for northwest and north-central parts of the forecast area. No accumulations of significance are expected. Cold air advection with north winds and clouds will make for a much cooler day on Thursday, with highs about 5 degrees Fahrenheit below normal. The next lee trof develops on Friday, with southwest winds bringing warmer conditions. On Saturday, the lee trof is expected to deepen rapidly, inducing southwest winds of 20 to 30 MPH, with highs 10 to 15 degrees above climo. A cold front arrives Saturday evening and Saturday night, with brisk north winds on Sunday causing Sunday to be another below-normal day, temperature- wise. Warming trend expected Monday through Wednesday. 03 Cockrell FIRE WEATHER... Elevated fire weather conditions will continue through the late afternoon today across the Panhandles until north winds diminish. Light to moderate north winds are expected on Thursday. Light to moderate southwest winds resume on Friday. Dry southwest winds increase notably on Saturday, leading to elevated to critical fire weather conditions across all of the Panhandles. Winds will shift to north as a cold front passes Saturday evening and Saturday night. Brisk north winds are expected on Sunday. Light to moderate southwest winds resume on Monday. Light winds are expected on Tuesday. Light to moderate southwest winds are expected on Wednesday. 03 && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$