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MD 1933 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHEAST WYOMING INTO EXTREME NORTHEAST COLORADO...FAR SOUTHWESTERN SOUTH DAKOTA AND THE NEBRASKA PANHANDLE
Mesoscale Discussion 1933 NWS Storm Prediction Center Norman OK 0314 PM CDT Thu Aug 10 2023 Areas affected...portions of southeast Wyoming into extreme northeast Colorado...far southwestern South Dakota and the Nebraska Panhandle Concerning...Severe potential...Watch unlikely Valid 102014Z - 102245Z Probability of Watch Issuance...5 percent SUMMARY...A couple instances of severe hail/wind may accompany the stronger storms. A WW issuance is not expected. DISCUSSION...Convective initiation/intensification is underway across the Higher Terrain of WY/CO. Ahead of the developing storms, a well-mixed boundary layer has materialized, characterized by 30 F surface temperature/dewpoint spreads and 9-10 C/km 0-3 km lapse rates (per 20Z mesoanalysis). Forecast soundings depict around 500 J/kg of tall/thin MLCAPE, distributed in roughly the 700-300 mb layer. Given elongated hodographs, storms that can mature in this environment may produce a couple instances of severe hail/wind. However, the severe threat should be sparse and a WW issuance is not anticipated. ..Squitieri/Guyer.. 08/10/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...UNR...GLD...BOU...CYS... LAT...LON 40140221 40290348 40450419 40930471 41900547 42770588 43240579 43460519 43540445 43400372 43050327 42420276 41750235 40960217 40140221 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0245 PM CDT Thu Aug 10 2023 Valid 102000Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE MID MISSOURI VALLEY AND VICINITY... ...SUMMARY... Isolated severe thunderstorms remain possible over parts of the eastern and central states this afternoon into tonight, including eastern North Carolina/southeast Virginia and parts of the Upper Midwest vicinity. ...Discussion... The main outlook adjustment being implemented in this update, aside from minor/local tweaks of the areal outlines, is an expansion of MRGL risk across the Iowa vicinity. Expectations are that an at least loosely organized MCS will move across the Iowa vicinity overnight, and that local/low-end severe potential may accompany the strongest cells. Otherwise, no appreciable changes appear necessary at this time. ..Goss.. 08/10/2023 .PREV DISCUSSION... /ISSUED 1139 AM CDT Thu Aug 10 2023/ ...Eastern Carolinas/southeast Virginia... A convectively augmented shortwave trough over the southern/central Appalachians will continue eastward today. A cluster of thunderstorms, likely MCV aided, is ongoing across coastal areas of the Carolinas at late morning. Although considerable cloud cover immediately preceding the cluster may be a thermodynamic hindrance, more appreciable destabilization is expected in more immediate coastal areas. Where storms intensify, a seasonally strong/cyclonically curved belt of westerlies (50+ kt at 500 mb) would support organized storms including the possibility of a few supercells and well-organized/moderately fast-moving clusters capable of wind damage and some tornado risk. Although uncertain, there is a scenario is which a secondary round of regional convective development occurs late this afternoon near the southeastward-moving weak front and/or preceding surface trough. While deep-layer shear will tend to weaken late this afternoon/early evening, wind profiles should conditionally remain supportive of well-organized storms, potentially including a few supercells. This could yield some storms capable of damaging winds, hail, and possibly a tornado, prior to the risk abating/shifting offshore by mid-evening. ...Dakotas/Upper Midwest and eastern Nebraska... As a mid/upper ridge shifts east, a low-amplitude trough will overspread the northern Great Plains. This will help induce a weak surface cyclone over western North Dakota with a surface trough arcing south into central Nebraska and a warm front extending southeast through southern Minnesota. Relatively modest boundary-layer moisture and deep-layer shear will be limiting factors to a more prolific severe threat across the region. But steeper mid-level lapse rates within an elevated mixed layer will spread east across most of South Dakota and much of Nebraska by early evening and support a confined corridor of moderate buoyancy with MLCAPE of 1000-2000 J/kg. Effective bulk shear of 25-35 kts should support a mixed mode of a few supercells and multicell clusters. The most likely zone for scattered thunderstorm development in the late afternoon should be near the surface trough/warm front intersection in the northeast South Dakota border area with ND/MN. Increasingly isolated development should trail south along the trough. A mix of large hail and severe wind gusts will be the main threats, with some potential that an MCS evolves and continues southeastward this evening. ...Mid-South/Tennessee Valley... Modifying outflow from early day thunderstorms should serve as a focus for redevelopment later this afternoon, along the remnant front to the north. Additionally, another round of low-level warm theta-e advection-driven storms should occur after sunset tonight. A modest combination of mid-level lapse rates and vertical shear should support a mainly isolated severe threat, with sporadic instances of damaging gusts and marginal hail possible. ...Coastal Mid-Atlantic/southern New England... Low-level warm theta-e advection will strengthen today and translate northeast from the Mid-Atlantic across New England this afternoon and evening. Low-topped convection (perhaps void of lighting flashes in some cases) should develop amid meager surface-based instability as thermodynamic profiles become saturated. Aside from localized wind damage, the potential for a brief tornado also exists owing to enlarged low-level hodograph curvature. ...Central High Plains... Isolated high-based thunderstorms should develop off the higher terrain of southeast Wyoming and far north-central Colorado near a lee surface trough. A deep mixed boundary layer along the adjacent High Plains could support a few severe wind gusts during the late afternoon to early evening. ...West-central/northwest Texas... Hot surface temperatures along the dryline may support isolated thunderstorm development late this afternoon and early evening. Should deep convection become sustained, the very deeply mixed boundary layer could yield a few severe-caliber wind gusts. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0247 PM CDT Thu Aug 10 2023 Valid 111200Z - 121200Z There are no changes needed to the current D2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 08/10/2023 .PREV DISCUSSION... /ISSUED 0152 AM CDT Thu Aug 10 2023/ ...Synopsis... Fire weather concerns will persist across parts of Texas on Friday with more localized concerns possible over northern Montana. Broad northwesterly flow aloft over the northern half of the country will continue to support breezy conditions at the surface. Across the southern CONUS, monsoonal thunderstorms are expected across the Southwest with another day of anomalously hot temperatures over the southern Plains. ...Texas... Weak lee troughing along the High Plains will induce a broad southerly flow regime across the southern Plains. This will advect unseasonably hot temperatures northward into northwest TX/western OK where high temperatures are expected to peak near 105 F. Forecast guidance suggests winds will be regionally augmented in proximity to a thermal low over northwest TX and/or the TX Panhandle, which will increase the fire weather potential. Maximum sustained winds near 15 mph appear probable with afternoon RH in the 20-30% range. Recent reports from the region indicate that these wind/RH conditions are sufficient for active fire behavior, warranting highlights. Thunderstorms developing along the lee trough and/or in proximity to the low will pose a threat for gusty outflow winds and perhaps dry lightning strikes (ensemble guidance shows low probability for wetting rainfall Friday afternoon). ...Northern Montana... Dry northwesterly low to mid-level flow will persist across north-central MT from Thursday into Friday afternoon. A few deterministic solutions suggest that elevated fire weather conditions are possible with 15-20 mph winds and RH values falling into the low 20s. However, ensemble guidance shows considerably more spread in the wind/RH forecast with limited probability for sustained elevated conditions. This hinders confidence in a robust fire threat, but receptive fuels over northern MT will support a fire concern if confidence in elevated conditions improves. ...Dry Thunderstorms... Monsoonal moisture will linger across AZ into western NM with decreasing column moisture with northern extent into NV, UT, and CO. While wetting thunderstorms are probable across the Southwest, PWAT values between 0.5 to 0.75 inches over the Great Basin/central Rockies will support another day of dry thunderstorm potential. Upper ridging over the region will limit broad scale ascent, but orographic lift will be sufficient for isolated thunderstorms. Although current fuel moisture values are sufficiently high to preclude a more robust fire concern, fuel trends will be monitored and may necessitate highlights if they become sufficiently receptive to lightning starts. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 101836
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Thu Aug 10 2023

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

Central East Pacific:
A tropical wave continues to produce a large area of disorganized
showers and thunderstorms several hundred miles south-southwest of
the coast of southwestern Mexico. Environmental conditions appear
conducive for gradual development of this system, and a tropical
depression is likely to form late this weekend or early next week
while it moves westward at about 15 mph across the central portion
of the basin.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...high...80 percent.

Western East Pacific:
Another tropical wave located well to the southwest of the southern
tip of the Baja California peninsula is producing some disorganized
showers and thunderstorms. Some slow development of this system is
possible during the next several days while it moves generally
westward at 10 to 15 mph across the far western portion of the basin
and into the Central Pacific basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

Off the Coast of Southern Mexico:
An area of low pressure is forecast to form offshore of Central
America in a few days. Environmental conditions are expected to be
conducive for gradual development of this system, and a tropical
depression could form during the early or middle part of next week
while it moves generally west-northwestward, roughly parallel to the
coast of southern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...50 percent.

$$
Forecaster Reinhart

Water users in the City of Galveston were asked to conserve water as demand between 4 a.m. and 8 a.m. was excessive, due to lawn irrigation amid the extreme heat and drought. Water use has been highest on the island’s West End. KRIV FOX 26 Houston (Texas), Aug 9, 2023

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1234 PM CDT Thu Aug 10 2023 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MID AND UPPER MISSISSIPPI AND LOWER MISSOURI VALLEYS... ...SUMMARY... Severe thunderstorms capable of large hail, damaging gusts, and perhaps a tornado or two are possible across portions of the Mid and Upper Mississippi Valley and Lower Missouri Valley areas on Friday. ...Mid and Upper Mississippi/Lower Missouri Valleys... Ongoing thunderstorms -- and some lingering severe potential -- are expected at the start of the period over the southern Wisconsin/eastern Iowa/northwestern Illinois/northern Missouri vicinity. This convection is forecast to continue moving east/southeastward across the central Illinois vicinity through midday. The strongest storms may be capable of producing locally damaging winds and marginal hail. Over southern portions of the SLGT risk area -- i.e. the Mid Mississippi and Lower Missouri Valleys and vicinity -- redevelopment of convection near a roughly west-to-east outflow is expected during the afternoon, and continuing into the evening (aided by southwesterly low-level jet development). With moderate (30 to 40 kt) mid-level northwesterlies, organized/locally severe storms are expected, with locally damaging wind gusts and hail expected. Risk may persist into the overnight hours as storms move southeastward. Farther north, over the Upper Mississippi Valley area, afternoon storm redevelopment is expected, as short-wave mid-level troughing shifts southeastward out of Canada. With daytime heating resulting in ample destabilization, and strong (40 to 50 kt) mid-level northwesterly flow, organized storms capable of producing locally damaging wind gusts and hail are expected to evolve, spreading eastward/southeastward through the evening. Local risk may extend as far east as Lower Michigan into the overnight hours. ...The Southeast... As a weak short-wave trough crosses the Southeast, and a very weak/outflow-reinforced surface front lingers, afternoon heating of the moist boundary layer in place will result in moderate destabilization. This will help to foster redevelopment of storms from the central Gulf Coast states eastward to the southern Atlantic Coast. With moderate lower- to mid-level west-southwesterly flow (around 30 kt), some potential for upscale linear growth/forward propagation is evident, which suggests strong/gusty winds across the area, including a few gusts which may approach severe levels during the afternoon and into the evening hours. ..Goss.. 08/10/2023 Read more

Drought in Texas has dried up grass and depleted stock tanks as the state endured record heat. The owner of a feed and supply store in Tennessee Colony reported that ranchers were getting feed deliveries in early August rather than mid-November as they usually do. Reuters (New York), Aug 10, 2023

The Brazos River Authority notified customers of a Stage 2 drought warning for communities getting water from Lake Stillhouse Hollow and Lake Georgetown. Water conservation was needed because the amount of water stored in the lakes was declining. Stage 2 restrictions require a reduction in water use of 10%. KXAN Online (Austin, Texas), Aug 4, 2023

Since water restriction enforcement began in the city of Wichita Falls in mid-July, 59 citations were issued through the municipal court system. Texoma’s Homepage (Wichita Falls, Texas), Aug 9, 2023

Drought delayed the ripening of apples at an orchard in Champaign, so harvest will occur later than usual. The pumpkins have taken longer to blossom. The opening of the pumpkin patch to visitors usually happens around Sept. 15, but may be pushed later into the month. WAND-TV (Champaign, Ill.), Aug 8, 2023

Gardening centers in Wichita Falls were educating customers about the watering needs of newly planted trees and shrubs and efficient watering methods. The city remained in stage 1 drought restrictions. KAUZ-TV CBS 6 Wichita Falls (Texas), Aug 9, 2023

The drought and heat of summer have led to higher demand for lawncare services such as irrigation, while pool construction has also remained busy. The president of a lawn care business stated that irrigation services had roughly doubled in 2023. A pool construction company has had an increase in demand of 25% to 50%. Even with additional workers, both businesses had a backlog. CBS News Minnesota (Minneapolis), Aug 9, 2023

Tomball entered stage 2 of its drought contingency plan as water demand exceeded 70% of production capacity for three consecutive days, triggering mandatory water restrictions. Tomball entered stage 1 in mid-July. Katy was also in stage 2 of its contingency plan. Houston Chronicle (Texas), Aug 9, 2023

MD 1922 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR THE RED RIVER VALLEY REGION
Mesoscale Discussion 1922 NWS Storm Prediction Center Norman OK 0520 PM CDT Wed Aug 09 2023 Areas affected...The Red River Valley region Concerning...Severe potential...Watch possible Valid 092220Z - 100015Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms developing along the Red River Valley will pose a risk for severe winds over the next several hours. Watch issuance is possible. DISCUSSION...Robust convective initiation is underway along a surface trough draped from eastern OK into north/northwest TX. 12 UTC soundings from OUN and FWD sampled high PWAT values generally near 1.75 inches, but recent surface observations are showing high dewpoint depressions on the order of 40-50 F. This suggests that the low-level thermodynamic environment is very deeply mixed and should support accelerating downdrafts. A mix of wet/dry downbursts appear possible with an attendant risk for severe winds. Trends will be monitored, and watch issuance is possible if it becomes evident the severe threat will be sufficiently widespread and persistent. ..Moore/Thompson.. 08/09/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SHV...TSA...FWD...OUN...SJT... LAT...LON 33159767 32589859 32239920 32089977 32310009 32679983 33419888 33959814 34249771 34629699 34709622 34639533 34019517 33439542 33289645 33159767 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0452 PM CDT Wed Aug 09 2023 Valid 111200Z - 171200Z ...Texas... Extremely dry and warm conditions, with daily highs 100+ F degrees, will continue across central and southern Texas through the extended period. While light rainfall will be possible across portions of southwest/north central Texas, much of central Texas will likely remain dry through D8. High pressure building in across the Four Corners to the Southern Plains will keep winds mostly light, though locally breezy conditions may occur. Elevated to locally Critical fire weather concerns will be likely daily, with low confidence in any one corridor where sustained winds will support Critical risk probabilities. Though the winds will largely stay below criteria, expect continued potential for new fire starts and rapid fire growth in hot and unstable conditions and extremely critically dry fuels. ...Pacific Northwest... Building high pressure will bring warming across the Pacific Northwest. Initial thunderstorm development will be possible as tropical moisture extends northward D4 - Saturday lingering into D7 - Tuesday (detailed below). Beyond the early week thunderstorm activity, thermal troughing may increase. This may lead to increased fire weather concerns in the extended. Confidence is low at this time in placement and strength and as a result impacts. ...Dry Thunderstorms... Potential remnants of tropical storm activity will spread northward into California and southern Oregon beginning D2 - Thursday through D3 - Friday. Recent model runs have been slower and drier with northern extent of the incoming moisture. Initial activity across central/northern California will likely be isolated, with low potential for a dry thunderstorm or two. Potential for thunderstorms will increase into D4 - Saturday and D5 - Sunday as better instability spreads across northern California. A mix of wet/dry storms with gusty and erratic winds may be possible. Confidence in coverage remains too low to include any areas at this time but this will be monitored in the coming days. ..Thornton.. 08/09/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0617 Status Updates
STATUS REPORT ON WW 617 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 SSE MKL TO 15 W CHA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1920 ..WEINMAN..08/09/23 ATTN...WFO...BMX...HUN...MEG...OHX... STATUS REPORT FOR WS 617 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC009-019-033-043-049-055-057-059-071-075-077-079-083-089-093- 095-103-127-133-092340- AL . ALABAMA COUNTIES INCLUDED ARE BLOUNT CHEROKEE COLBERT CULLMAN DEKALB ETOWAH FAYETTE FRANKLIN JACKSON LAMAR LAUDERDALE LAWRENCE LIMESTONE MADISON MARION MARSHALL MORGAN WALKER WINSTON MSC003-057-117-141-092340- MS . MISSISSIPPI COUNTIES INCLUDED ARE ALCORN ITAWAMBA PRENTISS TISHOMINGO Read more

WW 617 SEVERE TSTM AL MS TN 091850Z - 100100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 617 NWS Storm Prediction Center Norman OK 150 PM CDT Wed Aug 9 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Alabama Northeast Mississippi Middle Tennessee * Effective this Wednesday afternoon and evening from 150 PM until 800 PM CDT. * Primary threats include... Scattered damaging wind gusts to 65 mph likely Isolated large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...Storms are expected to increase and intensify along a warm front/instability gradient across the region, with wind profiles supportive of a few supercells and bowing segments. The severe thunderstorm watch area is approximately along and 55 statute miles north and south of a line from 40 miles west northwest of Muscle Shoals AL to 50 miles north northeast of Gadsden AL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). 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 1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 28025. ...Guyer Read more

WW 0618 Status Updates
STATUS FOR WATCH 0618 HAS NOT BEEN ISSUED YET Read more

WW 618 TORNADO AR KS MO OK 092105Z - 100300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 618 NWS Storm Prediction Center Norman OK 405 PM CDT Wed Aug 9 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northwest Arkansas Far Southeast Kansas Southwest Missouri Eastern Oklahoma * Effective this Wednesday afternoon and evening from 405 PM until 1000 PM CDT. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 65 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...The air mass in the wake of storms earlier today continues to gradually destabilize, with severe storms expected to increase mainly near a front through late afternoon and early evening. Strong wind profiles will support initial supercells. The tornado watch area is approximately along and 65 statute miles east and west of a line from 40 miles north northeast of Springfield MO to 30 miles south southeast of Mcalester OK. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and 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. && OTHER WATCH INFORMATION...CONTINUE...WW 617... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 28025. ...Guyer Read more