Special Weather Statement, NWS Tulsa, OK

Area Forecast Discussion
National Weather Service Tulsa OK
210 PM CDT Tue May 18 2021

.DISCUSSION...
Convective complex currently located over far northeast Texas
will lift into southeast Oklahoma over the next couple of hours
with the potential for heavy rainfall and a limited severe threat.
Main instability axis remains south of the Red River and the
stronger portion of the MCS will likely track northeast through
the ARKLATX region during the remainder of the afternoon hours.
Further north across NE OK/NW AR, modest surface based heating has
allowed for a marginally unstable airmass to develop with limited
CIN. Still the potential for a few scattered showers/thunderstorms
to develop across aforementioned area this afternoon/evening.

Upper low, currently located east of the Four Corners region,
will begin to shift slowly east towards the area Wednesday into
Thursday. Although the exact timing of the heavier thunderstorm
activity remains challenging, relatively high pops will continue
through this time period. PWATs will also continue to increase
with highly anomalous values in the 1.50-1.75 inch range by
Thursday. Locally heavy rainfall will remain likely with any of
the stronger storms. Although FFG remains relatively high across
NE OK/NW AR, north of the current flood watch, still the potential
for localized flooding with any storms that train over the same
areas through Thursday.

Main upper wave will begin to lift northeast of the region Thursday
night into Friday with rain chances decreasing. Upper high will
then begin to build westward over the weekend into early next
week with unseasonably warm/humid conditions expected. Generally
stayed close to NBM guidance through this time period.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   66  78  65  78 /  70  60  60  70
FSM   66  78  66  79 /  60  70  70  60
MLC   64  77  65  77 /  80  70  70  80
BVO   63  77  64  77 /  60  50  50  70
FYV   63  77  63  77 /  60  70  60  50
BYV   64  75  64  79 /  60  70  60  50
MKO   64  76  64  76 /  70  60  60  70
MIO   64  76  65  77 /  70  60  60  60
F10   64  77  65  77 /  80  60  60  70
HHW   64  75  65  76 /  80  80  70  80

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through Thursday morning for OKZ049-053-073-075-076.

AR...None.
&&

LONG TERM....12

Hazardous Weather Outlook
National Weather Service Tulsa OK
1254 PM CDT Tue May 18 2021

ARZ001-002-010-011-019-020-029-OKZ049-053>076-191030-
Adair OK-Benton AR-Carroll AR-Cherokee OK-Choctaw OK-Craig OK-
Crawford AR-Creek OK-Delaware OK-Franklin AR-Haskell OK-Latimer OK-
Le Flore OK-Madison AR-Mayes OK-McIntosh OK-Muskogee OK-Nowata OK-
Okfuskee OK-Okmulgee OK-Osage OK-Ottawa OK-Pawnee OK-Pittsburg OK-
Pushmataha OK-Rogers OK-Sebastian AR-Sequoyah OK-Tulsa OK-Wagoner OK-
Washington OK-Washington AR-
1254 PM CDT Tue May 18 2021

...HEAVY RAINFALL AND SEVERE WEATHER POSSIBLE THIS AFTERNOON AND
TONIGHT...

This Outlook is for Northwest and West Central Arkansas as well as
much of Eastern Oklahoma.

.DAY ONE...This Afternoon and Tonight.
TORNADO.
	RISK...Limited.
	AREA...Southeast Oklahoma.
	ONSET...This Afternoon.

SEVERE THUNDERSTORM.
	RISK...Elevated.
	AREA...Eastern Oklahoma and Northwest Arkansas.
	ONSET...This Afternoon.

FLASH FLOOD.
	RISK...Limited.
	AREA...Southeast Oklahoma.
	ONSET...This Afternoon.

HEAVY RAIN.
	RISK...Significant.
	AREA...Eastern Oklahoma and Northwest Arkansas.
	ONSET...This Afternoon.

	AREA AT GREATEST RISK...Southeast Oklahoma.

DISCUSSION...
Thunderstorms currently across northern Texas will move into southeast
Oklahoma this afternoon, along with additional scattered development possible
further north. With surface boundaries in place, The greater potential for
severe weather will be across southeast Oklahoma where large hail
and damaging winds will be the primary threats.  An isolated tornado is also
possible with any storm that interacts with a localized boundary across
southeast Oklahoma. While a lower severe weather risk will be in place
further north, large hail and locally damaging winds will also be the
primary threats.

Abundant moisture over the region will also allow for periods of
heavy rainfall through tonight. Widespread 1 to 2 inches and
locally greater will be possible across parts of southeast
Oklahoma, where a flood watch is in effect. Further north,
lesser amounts in the half inch to locally over one inch range
are possible. This rainfall on top of recent rains will increase
flash as well as river flooding concerns.

SPOTTER AND EMERGENCY MANAGEMENT ACTION STATEMENT...
Activation of the Regional Spotter Network Likely.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.
WEDNESDAY...Thunderstorm Potential...Heavy Rain Potential.
THURSDAY THROUGH SATURDAY...Thunderstorm Potential.
SUNDAY AND MONDAY...No Hazards.

EXTENDED DISCUSSION...
Widespread showers and thunderstorms are forecast to be ongoing
across the region Wednesday morning with additional storm
development possible into Wednesday night. Again, periods of heavy
rainfall will be possible and combined with forecast rains Tuesday
will continue to increase flooding and river flooding concerns. A
limited severe weather potential may remain possible as well
Wednesday. Shower and thunderstorms chances continue through the
end of the week before a low pressure system currently to the west
finally weakens and lifts off to the northeast. A ridge of high
pressure expands into the region over the weekend allowing for
precipitation chances to retreat westward and a warming trend to
develop over eastern Oklahoma and Northwest Arkansas.

EMERGENCY MANAGEMENT PLANNING STATEMENT...
Continue to monitor updated forecasts as forecast rainfall
through Wednesday night could likely increase mainstem river
flooding concerns.

weather.gov/tulsa contains additional information.

Special Weather Statement
National Weather Service Tulsa OK
219 PM CDT Tue May 18 2021

OKZ049-053-181945-
Choctaw OK-Pushmataha OK-
219 PM CDT Tue May 18 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN PUSHMATAHA AND
CHOCTAW COUNTIES UNTIL 245 PM CDT...

At 219 PM CDT, a strong thunderstorm was located 6 miles southwest of
Goodland, moving northeast at 35 mph.

Wind gusts up to 50 mph will be possible with this storm.

Locations in or near the path include...
Hugo...                           Fort Towson...
Sawyer...                         Soper...
Kent...                           Goodland...
Messer...                         Hugo Lake State Park...
Grant...                          Ord...
Fallon...                         Apple...
Speer...                          Unger...
Gay...

LAT...LON 3387 9545 3388 9546 3389 9546 3387 9550
      3389 9551 3388 9554 3393 9556 3394 9560
      3391 9564 3391 9567 3388 9570 3390 9579
      3416 9580 3416 9578 3422 9578 3410 9522
      3387 9538
TIME...MOT...LOC 1919Z 202DEG 30KT 3395 9566