Flash Flood Warning 37, NWS Tulsa, OK

826 
WGUS74 KTSA 311651
FFSTSA

Flash Flood Statement
National Weather Service Tulsa OK
1151 AM CDT Mon Aug 31 2020

ARC033-047-131-OKC079-135-311701-
/O.EXP.KTSA.FF.W.0037.000000T0000Z-200831T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Crawford AR-Franklin AR-Sebastian AR-Le Flore OK-Sequoyah OK-
1151 AM CDT Mon Aug 31 2020

...FLASH FLOOD WARNING WILL EXPIRE AT NOON CDT TODAY FOR 
SOUTHWESTERN CRAWFORD, SOUTHWESTERN FRANKLIN, NORTHERN SEBASTIAN, 
SOUTHEASTERN SEQUOYAH AND NORTHEASTERN LE FLORE COUNTIES...

The heavy rain has ended and flash flooding is no longer expected to 
pose a threat in the near term. However, additional rainfall is 
forecast through tonight which could increase flash flooding 
conditions again. Please continue to heed remaining road closures.

LAT...LON 3535 9488 3553 9480 3532 9385 3532 9392
      3525 9392 3523 9394 3523 9403 3515 9403
      3533 9483 3537 9484

$$

Area Forecast Discussion
National Weather Service Tulsa OK
641 AM CDT Mon Aug 31 2020

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
Thunderstorms are ongoing across eastern Oklahoma and northwestern
Arkansas at the time of writing. A strong to severe storm was
moving into the vicinity of FSM. This storm will likely produce
brief gusty winds as it passes over the terminal. Spotty showers
and storms continue at most other terminals this morning. This
activity should gradually diminish by mid to late morning with
skies expected to clear. A brief period of clearing skies is
expected for the first half of the afternoon.

The afternoon and evening forecast for this TAF period remain
very uncertain at this time. A cold front will approach the area
from the west which will be the main trigger for thunderstorms
this afternoon. There is also the potential for an outflow
boundary originating from a storm complex near Kansas City that
will dive into the area which may provide additional lifting for
thunderstorms. The eventual setup up of these two fronts will
play a vital role when it comes to the location and duration of storms
this afternoon, evening, and overnight for the terminals. With
low confidence, opted to go with guidance that would slowly push
thunderstorms through all terminal sites this evening and
overnight resulting in several hours of thunderstorms. The 18Z TAF
issuance should have a better handle on what to expect this
evening and overnight in terms of the duration of thunderstorm
activity and when the lowest conditions could occur. As it stands
now, TEMPO groups were used to illustrate where confidence was a
little higher in terms of the lowest expected conditions from
thunderstorms.

Snider

&&

.PREV DISCUSSION... /Issued 327 AM CDT Mon Aug 31 2020/

DISCUSSION...
Widely scattered showers/thunderstorms starting to develop across
NE OK in response to approaching upper wave in stronger low level
jet axis. Moderate instability/fairly steep mid level lapse rates
coupled with deep layer shear around 35 knots will support a
large hail/damaging wind threat across portions of eastern
Oklahoma this morning. In addition, with PWAT around 2 inches,
locally heavy rainfall is likely in the stronger storms. This
activity will begin to shift east into northwest Arkansas this
morning and will likely begin to weaken as storms move into a more
stable air- mass.

Cold front will push into far northeast Oklahoma this afternoon
with atmosphere becoming very unstable as low level moisture pools
ahead of boundary with dew-points climbing in the upper 70s. Weak
surface low progged along boundary may back winds enough for a
limited tornado threat, however main threats will again be large
hail/damaging winds. Thunderstorms are expected to increase in
coverage through the evening hours with activity spreading into
southeast Oklahoma/northwest Arkansas. With rainfall rates in the
1-2 inch per hour range in the stronger storms, localized flooding
will be possible and a flash flood watch may be needed for some
areas, especially south of I-44 where FFG has been lowered from
the previous rainfall over the last few days.

Multiple rounds of thunderstorms with a heavy rainfall will remain
possible Tuesday into Wednesday as upper trough axis approaches
from the northwest with upper low moving over the Four Corners
region and into west Texas. More widespread flooding will be
possible during this time including some main-stem river flooding.
Depending on how quickly upper low progresses, precipitation
chances may continue across southeast Oklahoma/northwest Arkansas
Thursday with a few lingering showers into Friday across the
south as front pushes south of the Red River. Cooler and less
humid conditions expected over the weekend as weak surface ridge
axis remains over NW AR.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   92  72  84  71 /  40  70  80  60
FSM   90  73  83  72 /  70  60  90  70
MLC   91  72  82  70 /  50  70  90  80
BVO   91  68  84  68 /  40  70  80  50
FYV   87  68  81  68 /  60  70  90  60
BYV   89  69  83  69 /  60  70  90  60
MKO   88  71  82  70 /  70  60  90  70
MIO   88  69  83  69 /  60  70  90  40
F10   90  70  82  69 /  60  70  90  70
HHW   92  73  84  72 /  60  80  80  80

&&

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

AVIATION.....21

Hazardous Weather Outlook
National Weather Service Tulsa OK
455 AM CDT Mon Aug 31 2020

ARZ001-002-010-011-019-020-029-OKZ049-053>076-011000-
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-
455 AM CDT Mon Aug 31 2020

...SEVERE WEATHER LIKELY TODAY...

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

.DAY ONE...Today and Tonight.

TORNADO.
	RISK...Limited.
	AREA...Northeast Oklahoma.
	ONSET...Late afternoon.

SEVERE THUNDERSTORM.
	RISK...Elevated.
	AREA...Eastern Oklahoma and northwest Arkansas.
	ONSET...Ongoing.

FLASH FLOOD.
	RISK...Limited.
	AREA...Eastern Oklahoma and northwest Arkansas.
	ONSET...Late Afternoon.

HEAVY RAIN.
	RISK...Elevated.
	AREA...Eastern Oklahoma and northwest Arkansas.
	ONSET...Ongoing.

DANGEROUS HEAT.
	RISK...Elevated.
	AREA...Eastern Oklahoma and west-central Arkansas.
	ONSET...This afternoon.

DISCUSSION...
Clusters of strong to severe thunderstorms have developed early
this morning across portions of northeast Oklahoma and west-
central Arkansas. Large hail and damaging winds will be likely in
the stronger clusters. Storms are expected to weaken around mid
morning as the low level jet begins to decrease.

Additional severe thunderstorm development is expected across portions
of northeast Oklahoma by late afternoon or early evening as a cold
front moves into the area. This activity will likely spread into
southeast Oklahoma and northwest Arkansas this evening into the
overnight hours with large hail and damaging winds. In addition,
very heavy rainfall is likely with localized flash flooding. A
flash flood watch may be issued later today as the axis of heavy
rainfall becomes more certain.

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

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.
TUESDAY...Severe Thunderstorm Potential...Heavy Rain Potential.
WEDNESDAY...Thunderstorm Potential...Heavy Rain Potential.
THURSDAY AND FRIDAY...Thunderstorm Potential.
SATURDAY...No Hazards.
SUNDAY...Thunderstorm Potential.

EXTENDED DISCUSSION...
The unsettled weather pattern will continue on Tuesday and Wednesday
as an upper level trough approaches from the northwest. Multiple
rounds of strong thunderstorms with very heavy rainfall will be
possible including the potential for flash flooding. Main-stem
river flooding may also become an issue as more widespread rainfall
occurs over the duration of the event.

weather.gov/tulsa contains additional information.

Special Weather Statement
National Weather Service Tulsa OK
501 AM CDT Mon Aug 31 2020

ARZ019-029-OKZ068-069-072-074-076-311045-
Sebastian AR-Crawford AR-Haskell OK-Adair OK-Sequoyah OK-Cherokee OK-
Le Flore OK-
501 AM CDT Mon Aug 31 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CRAWFORD...WESTERN
SEBASTIAN...NORTHEASTERN HASKELL...SEQUOYAH...SOUTHWESTERN ADAIR...
NORTHEASTERN LE FLORE AND SOUTHEASTERN CHEROKEE COUNTIES UNTIL 545 AM
CDT...

At 501 AM CDT, strong thunderstorms were located along a line
extending from 2 miles west of Brushy Lake State Park to 4 miles
south of Roland. Movement was southeast at 30 mph.

Penny size hail and winds in excess of 40 mph will be possible with
these storms.

Locations in or near the path include...
Fort Smith...                     Van Buren...
Sallisaw...                       Cedarville...
Greenwood...                      Alma...
Barling...                        Pocola...
Muldrow...                        Roland...
Lavaca...                         Spiro...
Arkoma...                         Mansfield...
Hackett...                        Huntington...
Bonanza...                        Midland...
Gans...                           Marble City...

This includes the following highways,
 Interstate 40 in Arkansas between mile markers 0 and 15.
 Interstate 40 in Oklahoma between mile markers 297 and 328.
 Interstate 540 between mile markers 1 and 14.
 Interstate 49 near mile marker 22.

LAT...LON 3508 9420 3508 9422 3506 9425 3506 9423
      3500 9423 3536 9497 3573 9492 3549 9416
TIME...MOT...LOC 1001Z 317DEG 26KT 3555 9487 3535 9453

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
523 AM CDT MON AUG 31 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0500 AM     TSTM WND GST     5 SSE HASKELL           35.75N 95.64W
08/31/2020  M56 MPH          MUSKOGEE           OK   MESONET

&&

SNIDER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
542 AM CDT MON AUG 31 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0534 AM     TSTM WND GST     2 S MUSKOGEE            35.72N 95.37W
08/31/2020  M59 MPH          MUSKOGEE           OK   ASOS

            MEASURED AT DAVIS FIELD JUST SOUTH OF MUSKOGEE.

&&

SNIDER

Special Weather Statement
National Weather Service Tulsa OK
549 AM CDT Mon Aug 31 2020

OKZ068-069-311115-
Adair OK-Cherokee OK-
549 AM CDT Mon Aug 31 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN ADAIR AND SOUTHEASTERN
CHEROKEE COUNTIES UNTIL 615 AM CDT...

At 549 AM CDT, a strong thunderstorm was located 5 miles northwest of
Bunch, moving east at 25 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

Locations in or near the path include...
Bunch...                          Cookson...
Cherokee Landing State Park...

LAT...LON 3564 9457 3564 9473 3568 9496 3583 9488
      3575 9453
TIME...MOT...LOC 1049Z 283DEG 23KT 3574 9482

Special Weather Statement
National Weather Service Tulsa OK
716 AM CDT Mon Aug 31 2020

ARZ029-OKZ076-311300-
Sebastian AR-Le Flore OK-
716 AM CDT Mon Aug 31 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN SEBASTIAN AND EAST
CENTRAL LE FLORE COUNTIES UNTIL 800 AM CDT...

At 716 AM CDT, strong thunderstorms were located along a line
extending from 5 miles west of Hartford to 3 miles southeast of Lake
Wister State Park. Movement was east at 20 mph.

Winds of 40 to 50 mph will be possible with these storms.

Locations in or near the path include...
Heavener...                       Howe...
Heavener Runestone State Park...  Hodgen...

A Severe Thunderstorm Watch remains in effect until 200 PM CDT for
west central Arkansas...and southeastern Oklahoma.

LAT...LON 3495 9435 3496 9436 3496 9437 3494 9439
      3495 9441 3493 9443 3493 9445 3474 9446
      3490 9478 3504 9446 3495 9434
TIME...MOT...LOC 1216Z 284DEG 18KT 3500 9448 3489 9471

Special Weather Statement
National Weather Service Tulsa OK
746 AM CDT Mon Aug 31 2020

ARZ029-311300-
Sebastian AR-
746 AM CDT Mon Aug 31 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL SEBASTIAN COUNTY
UNTIL 800 AM CDT...

At 746 AM CDT, a strong thunderstorm was located 3 miles northeast of
Oliver, moving east at 40 mph.

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

Locations in or near the path include...
Mansfield...                      Liberty...

A Severe Thunderstorm Watch remains in effect until 200 PM CDT for
west central Arkansas.

LAT...LON 3496 9427 3496 9433 3495 9434 3495 9435
      3496 9436 3508 9432 3507 9424 3506 9425
      3506 9423 3497 9423
TIME...MOT...LOC 1246Z 283DEG 36KT 3497 9423