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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0324 PM CDT Wed Sep 20 2023 Valid 221200Z - 281200Z ...Day 3/Friday... A strong westerly mid/upper-level jet streak, accompanying a deep midlevel low tracking eastward across the northern Rockies, will impinge on the central Rockies and adjacent High Plains on Day 3/Friday. A related surface low will deepen over the KS/CO border, yielding a tightening surface pressure gradient across the region. Downslope warming/drying (10-15 percent RH) over northeast NM, the western TX/OK Panhandles, and southeastern CO, combined with breezy/gusty westerly surface winds, will support elevated to locally critical fire-weather conditions. The primary limiting factor is marginal fuels across the area, precluding 70-percent Critical probabilities. Beyond Day 3/Friday, the potential for critical meteorological conditions over dry fuels appears low. ..Weinman.. 09/20/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Wed Sep 20 2023 Valid 202000Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHEAST OKLAHOMA INTO NORTHEAST TEXAS...AND OVER PARTS OF THE NORTHERN GREAT BASIN... ...SUMMARY... Strong storms capable of hail and gusty winds are possible across parts of southeastern Oklahoma and northeast Texas through this evening. Gusty winds may also accompany a few storms over the northern Great Basin. ...OK/TX... A very conditional risk for a strong/severe storm through early evening continues across parts of southeast OK into northeast TX. The Marginal (level 1 of 5) risk area has been trimmed from portions of eastern OK into western AR and far northeast TX. Persistent clouds and showers/thunderstorms have limited heating much of the day. Southwestern portions of the Marginal risk area have largely cleared out this afternoon and allowed temperatures to warm into the upper 70s to mid 80s. However, quite a bit of inhibition remains. Furthermore, HRRR and RRFS guidance shows little convective development this afternoon/evening. Some cumulus development is noted closer to the I-35 corridor amid stronger instability and weaker inhibition. Nebulous large-scale ascent may be insufficient to overcome this inhibition. However, if a storm can develop near the western edge of the Marginal risk and track southeast along residual outflow, a risk for hail and strong gusts could occur for a few hours. ...NV/UT/ID/WY... No changes have been made with the 20z update. See previous discussion below for more details. ..Leitman.. 09/20/2023 .PREV DISCUSSION... /ISSUED 1109 AM CDT Wed Sep 20 2023/ ...OK/AR/TX/LA... A persistent nocturnal MCS is weakening over western AR, with clearing skies over eastern OK in its wake. Strong heating will help yield a moderately unstable air mass by late afternoon across southeastern OK, where there will be some chance of a thunderstorm or two. Effective shear values of 40-50 knots and steep mid-level lapse rates will support a risk of large hail and damaging winds in any persistent storm that develops. However, weakening large scale support and a residual cap suggest the risk of initiation is rather low in the primary instability region. ...NV/UT/ID/WY... A rather dynamic upper trough is digging quickly southeastward today across the Pacific Northwest region. This will allow large scale ascent to overspread much of the northern Great Basin by this afternoon. A corridor of mid-level moisture ahead of the trough extends from northern NV into northwest WY, and should be favorable for the development of scattered high-based showers and thunderstorms later today. Skies are currently clear in this region, allowing steep low-level lapse rates to develop. As winds aloft strengthen this afternoon, the potential will exist for gusty/damaging wind gusts in a few of the fast-moving storms. Read more

107
ABPZ20 KNHC 201752
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Sep 20 2023

For the eastern North Pacific...east of 140 degrees west longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Kenneth, located about 1000 miles west-southwest of the
southern tip of the Baja California peninsula.

Western East Pacific (EP96):
An area of low pressure well southeast of the Hawaiian Islands is
producing disorganized showers and thunderstorms. Some gradual
development of this system is possible late this week and over the
weekend while it moves generally westward into the Central Pacific
basin.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

Central East Pacific:
An area of low pressure is expected to form in a couple of days
well southwest of the southern tip of the Baja California
peninsula. Some slow development of this system is possible this
weekend, and a tropical depression could form by early next week
while it moves westward to west-northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Hagen/Roberts

Residents and business owners of Tampa were encouraged to use water wisely as the area endured ongoing drought, an abnormal rainy season and a significant increase in water use. Water demand within city limits has been about 4 million gallons more daily than at this time of year in the past. Tampa was buying additional water from Tampa Bay Water, the city’s wholesale water provider. WTSP 10 Tampa Bay (Fla.), Sept 20, 2023

Large cracks and holes on the fields at Ramon Lucio ballpark in San Marcos were blamed on the drought. Fields were not safe to use, so the Parks and Recreation department opted to delay play on Monday, Sept. 18. The rest of the park was still open. FOX 7 Austin (Texas), Sept 19, 2023

The cranberry harvest in Wisconsin may be tricky for growers because little rain has fallen, leaving pond levels down. WAOW-ABC 9-Wausau (Wis.), Sept 19, 2023

A burn ban was issued for York County and will be in effect from Sept. 21 through Oct. 5. The county also had burn bans in April and June. York Dispatch (Pa.), Sept. 19, 2023

Allamakee County was the 18th county in Iowa and the 11th county in the northeast part of the state to adopt a burn ban. Allamakee County’s ban took effect on Sept. 12. Waukon Standard (Iowa), Sept 20, 2023 Burn bans were in effect for 16 Iowa counties as drought and continuing dry conditions affected the region. Open burning was prohibited. KGAN-TV CBS 2 (Cedar Rapids, Iowa), Sept. 8, 2023

000
ABPZ20 KNHC 192306
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Tue Sep 19 2023

For the eastern North Pacific...east of 140 degrees west longitude:

Active Systems:
The National Hurricane Center is issuing advisories on recently
upgraded Tropical Storm Kenneth, located about 900 miles southwest
of the southern tip of the Baja California peninsula.

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Berg

MD 2164 CONCERNING SEVERE THUNDERSTORM WATCH 686... FOR NORTHWEST TEXAS AND WESTERN OKLAHOMA.
Mesoscale Discussion 2164 NWS Storm Prediction Center Norman OK 0555 PM CDT Tue Sep 19 2023 Areas affected...Northwest Texas and western Oklahoma. Concerning...Severe Thunderstorm Watch 686... Valid 192255Z - 200030Z The severe weather threat for Severe Thunderstorm Watch 686 continues. SUMMARY...Increasing coverage and intensity of severe thunderstorms is expected through the evening. DISCUSSION...Showers which developed across the Texas Panhandle have intensified into supercells over the last hour as they moved into increasing instability (1500 J/kg MLCAPE). Effective shear of 40 to 45 knots per FDR VWP will continue to maintain the supercell threat through the evening. The long, relatively straight hodographs supports splitting supercells, the first of which has already occurred along the Texas/Oklahoma border east of Childress. Given moderate instability to the north of these ongoing storms, there may sufficient instability to support longer lived left-moving supercells capable of large to very large hail, particularly across southwest Oklahoma. ..Bentley.. 09/19/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...OUN...SJT...LUB...AMA...MAF... LAT...LON 32900070 33680061 34800021 35779936 36029885 36059816 35919752 34969739 33669768 32809812 32579908 32900070 Read more

WW 0686 Status Updates
STATUS REPORT ON WW 686 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..09/19/23 ATTN...WFO...OUN...LUB...AMA...SJT...FWD... STATUS REPORT FOR WS 686 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS OKC009-011-015-017-031-033-039-043-051-055-057-065-067-073-075- 137-141-149-192340- OK . OKLAHOMA COUNTIES INCLUDED ARE BECKHAM BLAINE CADDO CANADIAN COMANCHE COTTON CUSTER DEWEY GRADY GREER HARMON JACKSON JEFFERSON KINGFISHER KIOWA STEPHENS TILLMAN WASHITA TXC009-023-075-077-087-101-125-151-155-191-197-207-237-253-263- 269-275-337-345-417-429-433-447-485-487-503-192340- TX . TEXAS COUNTIES INCLUDED ARE ARCHER BAYLOR CHILDRESS CLAY COLLINGSWORTH COTTLE DICKENS FISHER FOARD HALL HARDEMAN HASKELL JACK JONES KENT KING KNOX MONTAGUE Read more

WW 686 SEVERE TSTM OK TX 192145Z - 200400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 686 NWS Storm Prediction Center Norman OK 445 PM CDT Tue Sep 19 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western Oklahoma Northwest Texas * Effective this Tuesday afternoon and evening from 445 PM until 1100 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Isolated severe thunderstorms are expected to develop through early evening and move southeast. Very large hail, possibly up to baseball size, and damaging winds will be possible. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 110 miles southwest of Wichita Falls TX to 60 miles north northeast of Clinton OK. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 28030. ...Bunting Read more

MD 2163 CONCERNING SEVERE THUNDERSTORM WATCH 686... FOR NORTH-CENTRAL TEXAS.
Mesoscale Discussion 2163 NWS Storm Prediction Center Norman OK 0520 PM CDT Tue Sep 19 2023 Areas affected...north-central Texas. Concerning...Severe Thunderstorm Watch 686... Valid 192220Z - 192345Z The severe weather threat for Severe Thunderstorm Watch 686 continues. SUMMARY...A supercell across north-central Texas could pose a large hail threat this evening. DISCUSSION...A supercell formed on the western periphery of mid-day elevated convection which moved east across north-central Texas. Given only weak CINH near this storm and its radar depiction over the last hour, this storm has likely rooted and is surface based in a region with around 1000 J/kg MLCAPE. 40+ knots of mid-level northwesterly flow (per FWD VWP) has yielded near 50 knots of effective shear. This environment will support supercells capable of large hail (potentially 2+ inches). If this storm continues to turn right, which it has started to do over the last 15 to 30 minutes, portions of at least the northern DFW metro area may be impacted by large to very large hail this evening. If this storm continues to maintain its current intensity or strengthen, an expansion of watch 686 may be needed. ..Bentley/Bunting.. 09/19/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD... LAT...LON 33649755 33609688 33189611 32739589 32469641 32599703 32869743 33099767 33269770 33649755 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0358 PM CDT Tue Sep 19 2023 Valid 211200Z - 271200Z On the backside of a midlevel cut-off low centered over portions of Oregon, a substantial mid/upper-level jet streak will overspread the West Coast on Day 3/Thursday. In the northern Sacramento Valley, boundary-layer mixing into the strong flow aloft, coupled with a tightening surface pressure gradient, will favor breezy/gusty surface winds and 10-15 percent RH on Day 3/Thursday. While this may yield elevated fire-weather conditions, confidence in the development of critical conditions is too low for probabilities at this time. Along the southeastern periphery of the midlevel low, strong deep-layer southwesterly flow will be in place across much of the Southwest into the central/southern Rockies on Days 3-5/Thursday-Saturday. A deeply mixed boundary layer across these areas will support 20+ mph sustained southwesterly surface winds and 15-20 percent RH. These meteorological conditions would typically warrant Critical probabilities, though ample rainfall and generally unreceptive fuels should limit the overall fire-weather threat. Beyond Day 5/Saturday, strong midlevel flow accompanying a mid/upper-level trough will overspread the northwestern CONUS, favoring strengthening surface winds across the region. While this may lead to an increase in fire-weather concerns, rainfall preceding this system and continued model disagreement limits confidence in the fire-weather threat. ..Weinman.. 09/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0358 PM CDT Tue Sep 19 2023 Valid 211200Z - 271200Z On the backside of a midlevel cut-off low centered over portions of Oregon, a substantial mid/upper-level jet streak will overspread the West Coast on Day 3/Thursday. In the northern Sacramento Valley, boundary-layer mixing into the strong flow aloft, coupled with a tightening surface pressure gradient, will favor breezy/gusty surface winds and 10-15 percent RH on Day 3/Thursday. While this may yield elevated fire-weather conditions, confidence in the development of critical conditions is too low for probabilities at this time. Along the southeastern periphery of the midlevel low, strong deep-layer southwesterly flow will be in place across much of the Southwest into the central/southern Rockies on Days 3-5/Thursday-Saturday. A deeply mixed boundary layer across these areas will support 20+ mph sustained southwesterly surface winds and 15-20 percent RH. These meteorological conditions would typically warrant Critical probabilities, though ample rainfall and generally unreceptive fuels should limit the overall fire-weather threat. Beyond Day 5/Saturday, strong midlevel flow accompanying a mid/upper-level trough will overspread the northwestern CONUS, favoring strengthening surface winds across the region. While this may lead to an increase in fire-weather concerns, rainfall preceding this system and continued model disagreement limits confidence in the fire-weather threat. ..Weinman.. 09/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0358 PM CDT Tue Sep 19 2023 Valid 211200Z - 271200Z On the backside of a midlevel cut-off low centered over portions of Oregon, a substantial mid/upper-level jet streak will overspread the West Coast on Day 3/Thursday. In the northern Sacramento Valley, boundary-layer mixing into the strong flow aloft, coupled with a tightening surface pressure gradient, will favor breezy/gusty surface winds and 10-15 percent RH on Day 3/Thursday. While this may yield elevated fire-weather conditions, confidence in the development of critical conditions is too low for probabilities at this time. Along the southeastern periphery of the midlevel low, strong deep-layer southwesterly flow will be in place across much of the Southwest into the central/southern Rockies on Days 3-5/Thursday-Saturday. A deeply mixed boundary layer across these areas will support 20+ mph sustained southwesterly surface winds and 15-20 percent RH. These meteorological conditions would typically warrant Critical probabilities, though ample rainfall and generally unreceptive fuels should limit the overall fire-weather threat. Beyond Day 5/Saturday, strong midlevel flow accompanying a mid/upper-level trough will overspread the northwestern CONUS, favoring strengthening surface winds across the region. While this may lead to an increase in fire-weather concerns, rainfall preceding this system and continued model disagreement limits confidence in the fire-weather threat. ..Weinman.. 09/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0358 PM CDT Tue Sep 19 2023 Valid 211200Z - 271200Z On the backside of a midlevel cut-off low centered over portions of Oregon, a substantial mid/upper-level jet streak will overspread the West Coast on Day 3/Thursday. In the northern Sacramento Valley, boundary-layer mixing into the strong flow aloft, coupled with a tightening surface pressure gradient, will favor breezy/gusty surface winds and 10-15 percent RH on Day 3/Thursday. While this may yield elevated fire-weather conditions, confidence in the development of critical conditions is too low for probabilities at this time. Along the southeastern periphery of the midlevel low, strong deep-layer southwesterly flow will be in place across much of the Southwest into the central/southern Rockies on Days 3-5/Thursday-Saturday. A deeply mixed boundary layer across these areas will support 20+ mph sustained southwesterly surface winds and 15-20 percent RH. These meteorological conditions would typically warrant Critical probabilities, though ample rainfall and generally unreceptive fuels should limit the overall fire-weather threat. Beyond Day 5/Saturday, strong midlevel flow accompanying a mid/upper-level trough will overspread the northwestern CONUS, favoring strengthening surface winds across the region. While this may lead to an increase in fire-weather concerns, rainfall preceding this system and continued model disagreement limits confidence in the fire-weather threat. ..Weinman.. 09/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Tue, 19 Sep 2023 20:36:17 GMT


Wind Speed Probabilities last updated Tue, 19 Sep 2023 21:29:25 GMT

Issued at 2100 UTC TUE SEP 19 2023 000 FOPZ13 KNHC 192035 PWSEP3 TROPICAL STORM KENNETH WIND SPEED PROBABILITIES NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132023 2100 UTC TUE SEP 19 2023 AT 2100Z THE CENTER OF TROPICAL STORM KENNETH WAS LOCATED NEAR LATITUDE 15.1 NORTH...LONGITUDE 121.0 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 40 KTS...45 MPH...75 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 18Z TUE AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 18Z TUE 06Z WED 18Z WED 06Z THU 18Z THU 18Z FRI 18Z SAT PERIODS TO TO TO TO TO TO TO 06Z WED 18Z WED 06Z THU 18Z THU 18Z FRI 18Z SAT 18Z SUN FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 125W 34 X 6( 6) 7(13) 1(14) X(14) X(14) X(14) 20N 125W 34 X 1( 1) X( 1) 2( 3) 1( 4) X( 4) X( 4) 20N 130W 34 X X( X) X( X) 1( 1) 3( 4) X( 4) X( 4) $$ FORECASTER HAGEN/PASCH

Issued at 200 PM PDT Tue Sep 19 2023 000 WTPZ43 KNHC 192035 TCDEP3 Tropical Storm Kenneth Discussion Number 2 NWS National Hurricane Center Miami FL EP132023 200 PM PDT Tue Sep 19 2023 SSMIS and GMI microwave overpasses from this morning around 13Z indicated that the cyclone was still quite disorganized. However, the satellite presentation has improved since that time. The earlier northeasterly to easterly shear appears to be abating. A 1714 UTC ASCAT-B pass confirms that the low-level center is underneath the central cold convective canopy and also shows tropical-storm-force winds up to 40 kt in the NW quadrant. Based on the ASCAT pass, the depression is upgraded to Tropical Storm Kenneth with 40-kt winds. Based on fixes over the past 6 hours, the center appears to have reformed a bit to the west. The estimated motion is 280/14. A west-northwestward motion is expected through Wednesday night as the cyclone is steered by the trade wind flow. After that time, a potent mid- to upper-level trough approaching from the northwest is expected to cause Kenneth to turn to the northwest or north-northwest. The track forecast was adjusted a bit faster and to the left of the previous NHC prediction, mainly due to the recent center reformation, which caused some of the simple consensus models to be farther west this cycle. The intensity forecast has been adjusted upward based on the higher initial intensity. Warm ocean temperatures, light northeasterly to easterly vertical wind shear, and a moist low to mid-level troposphere currently surround the tropical cyclone. The system has perhaps 36 hours to strengthen while it remains in these relatively favorable environmental conditions. The cyclone is forecast to cross the 26C SST isotherm in about 48 h. The aforementioned approaching mid- to upper-level trough will induce strong southwesterly vertical wind shear on the cyclone beginning by 60 h. After that time, much drier air along with further decreasing ocean temperatures and increasing wind shear will lead to the cyclone losing its convection and becoming a remnant low in about 3 to 4 days. Global models show the system opening up into a trough by Day 5. Given the hostile conditions the cyclone will be moving into, the NHC forecast follows suit and calls for dissipation by Day 5. FORECAST POSITIONS AND MAX WINDS INIT 19/2100Z 15.1N 121.0W 40 KT 45 MPH 12H 20/0600Z 15.4N 122.4W 45 KT 50 MPH 24H 20/1800Z 15.9N 124.1W 50 KT 60 MPH 36H 21/0600Z 16.4N 125.6W 50 KT 60 MPH 48H 21/1800Z 17.4N 126.6W 45 KT 50 MPH 60H 22/0600Z 19.0N 127.3W 35 KT 40 MPH 72H 22/1800Z 20.4N 127.8W 30 KT 35 MPH 96H 23/1800Z 22.3N 128.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 24/1800Z...DISSIPATED $$ Forecaster Hagen/Pasch