Alert archive / Oklahoma / Dense Fog Advisories in 2021

Dense Fog Advisory 3, NWS Tulsa, OK

February 27, 20219 counties in Oklahoma

NWS Tulsa, OK issued this dense fog advisory at Feb 27, 2021, 9:15 PM CST for 9 counties in Oklahoma. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued: Feb 27, 2021, 9:15 PM CST (03:15 UTC)
Expired: Feb 28, 2021, 3:28 AM CST
In force: 6 hr
Issued by: NWS Tulsa, OK

Counties Choctaw County, OK, Haskell County, OK, Latimer County, OK, McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Okmulgee County, OK, Pittsburg County, OK, Pushmataha County, OK

The radar

The Western Arkansas radar (KSRX), 115 km from the middle of the area, began a volume at 03:15 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 3.3 hours before the alert went out and 165 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 25 J/kg
Mixed-layer CIN: -143 J/kg
Mixed-layer LCL: 538 m above ground
0-6 km bulk shear: 74 kt
0-1 km storm-relative helicity: 430 m²/s²
0-3 km storm-relative helicity: 418 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tulsa, OK wrote its last area forecast discussion before this dense fog advisory went out at Feb 27, 5:39 PM CST, 3 hours 36 minutes earlier.

Area forecast discussion, Feb 27, 5:39 PM CST, 3 hours 36 minutes before

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Hazardous weather outlook, Feb 27, 5:03 PM CST, 4 hours 12 minutes before

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In the hours before

Special weather statement, Feb 27, 4:15 PM CST, 5 hours before

Special Weather Statement
National Weather Service Tulsa OK
415 PM CST Sat Feb 27 2021

OKZ068>070-072-074-272245-
Haskell OK-Adair OK-Muskogee OK-Sequoyah OK-Cherokee OK-
415 PM CST Sat Feb 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN HASKELL...
NORTHWESTERN SEQUOYAH...SOUTHERN ADAIR...SOUTHEASTERN CHEROKEE AND
SOUTHEASTERN MUSKOGEE COUNTIES UNTIL 445 PM CST...

At 415 PM CST, a strong thunderstorm was located over Tamaha, moving
northeast at 65 mph.

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

Locations in or near the path include...
Sallisaw...                       Vian...
Gore...                           Webbers Falls...
Marble City...                    Tamaha...
Brushy...                         Cookson...
Brushy Lake State Park...         Cherokee Landing State Park...
Bunch...                          Lake Tenkiller State Park...
Box...                            Mc Key...

This includes Interstate 40 in Oklahoma between mile markers 285 and
310.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3530 9492 3537 9524 3584 9493 3564 9448
TIME...MOT...LOC 2215Z 221DEG 55KT 3538 9496

Special weather statement, Feb 27, 4:45 PM CST, 4 hours 30 minutes before

Special Weather Statement
National Weather Service Tulsa OK
445 PM CST Sat Feb 27 2021

ARZ001-010-019-OKZ068-069-272315-
Benton AR-Washington AR-Crawford AR-Adair OK-Cherokee OK-
445 PM CST Sat Feb 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN BENTON...
NORTHWESTERN CRAWFORD...WASHINGTON...ADAIR AND SOUTHEASTERN CHEROKEE
COUNTIES UNTIL 515 PM CST...

At 443 PM CST, a strong thunderstorm was located 7 miles south of
Stilwell, moving northeast at 60 mph.

Penny size hail will be possible with this storm.

Locations in or near the path include...
Fayetteville...                   Springdale...
Siloam Springs...                 Stilwell...
Farmington...                     Prairie Grove...
Elkins...                         Tontitown...
West Fork...                      Lincoln...
Westville...                      Greenland...
West Siloam Springs...            Watts...
Adair State Park...               Christie...
Cincinnati...                     Maryetta...
Bunch...                          Baron...

This includes Interstate 49 between mile markers 51 and 71.

LAT...LON 3563 9447 3564 9448 3564 9493 3616 9458
      3616 9456 3618 9457 3616 9392
TIME...MOT...LOC 2243Z 224DEG 62KT 3572 9459

The office that day

Everything else NWS Tulsa, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 28, 10:33 AM CST	Severe Thunderstorm Warning	TSA	Choctaw, Pushmataha	42 min
Feb 28, 11:32 AM CST	Special Weather Statement	TSA	Choctaw	43 min
Feb 28, 11:39 AM CST	Severe Thunderstorm Warning	TSA	Choctaw, Pushmataha	38 min
Feb 28, 12:39 PM CST	Special Weather Statement	TSA	Choctaw	36 min
Feb 28, 12:52 PM CST	Severe Thunderstorm Warning	TSA	Choctaw, Pushmataha	23 min
Feb 28, 1:02 PM CST	Severe Thunderstorm Warning	TSA	Choctaw	28 min

Nearby

Dense Fog Advisories in Oklahoma, 2021 Dense Fog Advisories in Arkansas, 2021 Every dense fog advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.