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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Thu Jul 18 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS EASTERN NORTH CAROLINA INTO FAR SOUTHEAST VIRGINIA... ...SUMMARY... Isolated strong to severe thunderstorms are possible Thursday afternoon across parts of north-central Montana and the central and southern High Plains. Isolated to scattered severe thunderstorms are also expected from the southern Appalachians into eastern North Carolina. ...Synopsis... Early-morning surface observations show a diffuse cold front draped from the Mid-Atlantic region into the southern Plains. This feature is expected to slowly push south over the next 24 hours, as surface high pressure builds over the Plains/Midwest in the wake of an eastward-tracking upper wave. A reservoir of upper 60s to low 70s dewpoints lies to the south of the cold front, and while mid-level lapse rates are fairly modest (based on 00 UTC soundings), diurnal heating into the mid 80s should be sufficient to promote thunderstorm development along the front by early afternoon. Thunderstorm coverage is expected to be somewhat more focused across the southern Appalachians into the Carolinas, as ascent associated with a weak mid-level perturbation (currently over the mid-MS Valley) overspreads the region at peak heating. To the west, isolated to scattered thunderstorms appear likely within an upslope flow regime along the central Rockies and ahead of a shortwave trough over northern Montana. ...Carolinas... The synoptic cold front is currently forecast to be along the VA/NC border by around mid-day. Thunderstorm development along the front appears probable by around 18 UTC, as temperatures warm into the low 80s and ascent from a subtle mid-level impulse overspreads the region. Large hail may be an initial concern depending on storm coverage along the front, but storm motion and deep-layer shear vectors along and/or towards the cool side of the boundary will likely promote upscale growth by mid/late afternoon. As this occurs, the potential for strong to severe winds will increase downstream across eastern NC and far southeast VA. Latest CAM guidance shows reasonably good agreement in the development of a squall line, and while deep-layer shear will not be overly strong (around 25 knots), heating ahead of the line should yield moderate buoyancy with MLCAPE reaching up to 2500 J/kg that will promote robust convection capable of damaging gusts. The coverage of this threat appears sufficient to warrant higher (15%) wind risk probabilities. ...Central to southern High Plains... Another day of easterly upslope winds along the southern to central Rockies is anticipated as a surface high to the east builds. Latest upper-air analyses show the east slopes of the Rockies lie on the periphery of a plume of relatively steep (7+ C/km) lapse rates. This should support isolated to scattered thunderstorm development by mid to late afternoon. Adequate deep-layer shear will be in place to promote storm organization, including the potential for a supercell or two if more discrete storm modes can be realized. However, weak low-level storm-relative winds and steep low-level lapse rates will likely favor cold-pool driven storm propagation and the development of multiple convective clusters with an attendant severe-wind risk. ...Montana... A shortwave impulse is evident in early-morning water-vapor imagery across the Pacific Northwest. This feature is expected to crest the apex of a stout upper ridge over the next 24 hours. Advected precipitable water imagery shows a diluted plume of monsoonal moisture ahead of this wave, which should provide adequate mid-level moisture for thunderstorm development by late afternoon. While buoyancy will be very modest (around 500 J/kg SBCAPE), 30 knot mid-level flow atop easterly low-level winds should provide adequate deep-layer wind shear for some storm organization, most likely into somewhat cohesive clusters given deep-boundary layer mixing that will favor strong cold pool production. Such clusters may be capable of strong to severe winds as they push east across north-central MT. ..Moore.. 07/18/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Thu Jul 18 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS EASTERN NORTH CAROLINA INTO FAR SOUTHEAST VIRGINIA... ...SUMMARY... Isolated strong to severe thunderstorms are possible Thursday afternoon across parts of north-central Montana and the central and southern High Plains. Isolated to scattered severe thunderstorms are also expected from the southern Appalachians into eastern North Carolina. ...Synopsis... Early-morning surface observations show a diffuse cold front draped from the Mid-Atlantic region into the southern Plains. This feature is expected to slowly push south over the next 24 hours, as surface high pressure builds over the Plains/Midwest in the wake of an eastward-tracking upper wave. A reservoir of upper 60s to low 70s dewpoints lies to the south of the cold front, and while mid-level lapse rates are fairly modest (based on 00 UTC soundings), diurnal heating into the mid 80s should be sufficient to promote thunderstorm development along the front by early afternoon. Thunderstorm coverage is expected to be somewhat more focused across the southern Appalachians into the Carolinas, as ascent associated with a weak mid-level perturbation (currently over the mid-MS Valley) overspreads the region at peak heating. To the west, isolated to scattered thunderstorms appear likely within an upslope flow regime along the central Rockies and ahead of a shortwave trough over northern Montana. ...Carolinas... The synoptic cold front is currently forecast to be along the VA/NC border by around mid-day. Thunderstorm development along the front appears probable by around 18 UTC, as temperatures warm into the low 80s and ascent from a subtle mid-level impulse overspreads the region. Large hail may be an initial concern depending on storm coverage along the front, but storm motion and deep-layer shear vectors along and/or towards the cool side of the boundary will likely promote upscale growth by mid/late afternoon. As this occurs, the potential for strong to severe winds will increase downstream across eastern NC and far southeast VA. Latest CAM guidance shows reasonably good agreement in the development of a squall line, and while deep-layer shear will not be overly strong (around 25 knots), heating ahead of the line should yield moderate buoyancy with MLCAPE reaching up to 2500 J/kg that will promote robust convection capable of damaging gusts. The coverage of this threat appears sufficient to warrant higher (15%) wind risk probabilities. ...Central to southern High Plains... Another day of easterly upslope winds along the southern to central Rockies is anticipated as a surface high to the east builds. Latest upper-air analyses show the east slopes of the Rockies lie on the periphery of a plume of relatively steep (7+ C/km) lapse rates. This should support isolated to scattered thunderstorm development by mid to late afternoon. Adequate deep-layer shear will be in place to promote storm organization, including the potential for a supercell or two if more discrete storm modes can be realized. However, weak low-level storm-relative winds and steep low-level lapse rates will likely favor cold-pool driven storm propagation and the development of multiple convective clusters with an attendant severe-wind risk. ...Montana... A shortwave impulse is evident in early-morning water-vapor imagery across the Pacific Northwest. This feature is expected to crest the apex of a stout upper ridge over the next 24 hours. Advected precipitable water imagery shows a diluted plume of monsoonal moisture ahead of this wave, which should provide adequate mid-level moisture for thunderstorm development by late afternoon. While buoyancy will be very modest (around 500 J/kg SBCAPE), 30 knot mid-level flow atop easterly low-level winds should provide adequate deep-layer wind shear for some storm organization, most likely into somewhat cohesive clusters given deep-boundary layer mixing that will favor strong cold pool production. Such clusters may be capable of strong to severe winds as they push east across north-central MT. ..Moore.. 07/18/2024 Read more

000
ABPZ20 KNHC 180506
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Wed Jul 17 2024

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

Western East Pacific (EP92):
A broad area of low pressure located more than a thousand miles
west-southwest of the southern tip of the Baja California peninsula
continues to produce disorganized showers and thunderstorms well
removed from its center. Environmental conditions near the system
are becoming less conducive, with stronger upper-level winds and
cooler waters, and its window for further development is closing.
The low is forecast to move generally west-northwestward at about
10 mph across the western part of the basin.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent.

South of Southern Mexico:
An area of low pressure could form by this weekend a few hundred
miles south of the coast of southern Mexico. Thereafter, some slow
development of this system is possible by the middle of next week
while it moves westward to west-northwestward at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Papin

Iredell Water has implemented Stage Two Mandatory Water Shortage Condition restrictions due to ongoing severe and moderate drought conditions in Iredell County. Restrictions apply to lawn and landscape irrigation. Queen City News (NC), July 18, 2024.

Low water levels and high temperatures led to several hoot-owl restrictions in Montana taking effect July 12, 2024. Affected rivers included the Big Hole River, Smith River, East Gallatin River, Gallatin River, Madison River, Clark Fork River, Bitterroot River, Blackfoot River. Clark Fork Valley Press (Montana), July 18, 2024.

Arkansas rice farmers are saving up to 40% of their normal irrigation water using zero-grade farming. The practice involves using level ground to hold water longer than sloped land would. It can be costly to convert fields to zero-grade, among other barriers to adopting this practice. Arkansas Times (AR), July 17, 2024.

Invasive zebra mussels have declined in Lake Travis due to low water levels caused by drought. KXAN (Texas), July 18, 2024.

Drought-induced dryness has left Hawaii Volcanoes National Park vulnerable to fires, leading rangers to close some roads in the park. Fox Weather (NY), July 18. 2024.

Due to ongoing drought, farmers in West Virginia's Eastern Panhandle are hand-watering crops in places where irrigation is not possible. Many of their fields are not normally irrigated. MetroNews (West Virginia), July 18, 2024.

Years of drought and fires have benefitted California's fig orchards, according to the California Fresh Fig Growers Association. The 2024 season is starting early and may be one of the best California has seen. PRNewswire (New York), July 18, 2024.

The town of Round Hill, Virginia, has voted to impose mandatory water use restrictions in response to extreme drought conditions. The restrictions will prohibit most outdoor water use. Loudoun Now (Virginia), July 18, 2024.

Drought-weakened trees are falling in the DC area. NBC Washington (District of Columbia), July 18, 2024.

Water restrictions were implemented in the town of Strasburg due to a drought emergency declared by the town. Daily News-Record (Virginia), July 18, 2024.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 PM CDT Wed Jul 17 2024 Valid 180100Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MID-ATLANTIC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... The threat for damaging winds will continue this evening across portions of the Ohio and Tennessee River Valleys into the Mid-Atlantic. More isolated strong to severe thunderstorms are anticipated across parts of the central High Plains. ...Mid-Atlantic into the southern Appalachians/Tennessee Valley... A line of thunderstorms continue to push east towards the Mid-Atlantic coast as of 00 UTC. Latest RAP mesoanalysis continues to show adequate buoyancy and deep-layer shear immediately downstream for storm maintenance for the next 1-2 hours, but increasing MLCIN with the onset of nocturnal cooling and undercutting outflows (noted in some regional radar imagery) will likely result in a gradual weakening trend through late evening as storms reach the coast. To the west across the southern Appalachians and TN Valley, shallow convection continues to percolate along a cold front as synoptic ascent associated with the primary upper low to the north glances the region. Although the air mass across TN into the southern Appalachians has been convectively overturned to some degree over the past several hours, latest CAM guidance continues to suggest convection along the front may increase in coverage and intensity after 01 UTC with an attendant threat for sporadic damaging winds. ...Central High Plains... A loosely organized cluster of thunderstorms ongoing across northeast CO may pose a severe wind and hail threat for the next few hours, but a gradual weakening trend is expected later tonight due to a propensity for undercutting outflows and as storms migrate southward into an air mass that has already been processed by prior convection. To the south across far southwest KS, a cluster of thunderstorms may continue to propagate to the south along a buoyancy axis and pose a wind threat, but poor MLCAPE and weak hodograph structure observed in the 00 UTC DDC sounding suggest the potential for a more organized severe threat is limited. ..Moore.. 07/18/2024 Read more

A farmer in Cambria County, Pennsylvania, states that he has lost at least $50,000 in production due to drought this year. He says that there is very little irrigation in the area so local farmers are dependent on rainfall. WJAC6 (Johnstown, Pennsylvania), July 16, 2024.

Over 30 percent of pasture across the Southeast is rated as poor or very poor by the latest USDA-NASS reports. In Georgia, North Carolina, South Carolina, Virginia, and West Virginia, over 40 percent of pasture is rated as poor or very poor. Poor or very poor pasture is found in Tennessee at 37 percent, Kentucky at 19 percent, Mississippi at 18 percent, Arkansas at 16 percent, Alabama at 14 percent, Florida at 4 percent, and Louisiana at 3 percent. Beef Magazine (Saint Charles, Illinois), July 17, 2024.

000
ABPZ20 KNHC 172312
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Wed Jul 17 2024

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

Western East Pacific (EP92):
A broad area of low pressure located more than a thousand miles
west-southwest of the southern tip of the Baja California peninsula
is producing poorly-organized showers and thunderstorms. While a
short-lived tropical depression could still form during the next
day or so, the window for further development is closing with the
system expected to encounter stronger upper-level winds and cooler
waters by late Thursday. The low is forecast to move
west-northwestward at about 10 mph across the western part of the
basin.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

South of Southern Mexico:
An area of low pressure is likely to form this weekend a few hundred
miles south of the coast of southern Mexico. Some slow development
of this system is possible early next week while it moves westward
to west-northwestward at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Beven

Stage 2 (moderate) water restrictions have been enacted in Boyd due to increased demand for water the past few weeks. Since June 1, the City of Boyd has purchased an additional five million gallons of water to supplement their normal supply. Restrictions apply to sprinklers and automatic irrigation systems. Wise County Messenger (Texas), July 17, 2024.

Water restrictions have been issued in the City of Statesville, North Carolina, in response to Stage D2 Severe Drought conditions, as determined by the N.C. Drought Management Advisory Council. Restrictions apply to lawn watering, tree and bed irrigation, golf courses, athletic fields, vehicle washing, and washing of roads, sidewalks, and public buildings. Iredell Free News (Statesville, N.C.), July 16, 2024.