Aggregator

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Sat Aug 26 2023 Valid 281200Z - 031200Z ...D3/Mon - D5/Wed - Southern Plains... Dry and breezy post-frontal flow in the southern Plains will lead to an extended period of elevated to potentially critical fire weather conditions in a region with ongoing extreme to exceptional drought. Thunderstorms today and Sunday may improve fuel state in some localized regions, but it is not expected to be widespread enough to have a significant impact on fuel receptiveness. ...D3/Mon - D5/Wed - Northwest... A negatively tilted mid-level trough will start to proceed inland across the Pacific Northwest on Monday. As this occurs, some thunderstorms will be possible across the Cascade crests during the day and much of western Washington overnight. PWAT values are expected to be around 1 inch with storms likely more wet. However, storm speeds will be in excess of 30 mph, which could increase the threat for dry thunderstorms somewhat. As this trough advances east, some breezy conditions are expected in the higher terrain on the western slopes of the Cascades and through the Cascade gaps. The significant moisture surge with this system may keep relative humidity higher and thus keep the fire weather threat somewhat more subdued than otherwise may be expected. These dry and breezy conditions will expand into the Great Basin and Columbia Basin on Tuesday and Wednesday. At this time, no 40 percent probabilities have been added as relative humidity is forecast to stay 30%+ where fuel are critically dry. ...D4/Tue - D5/Wed - Montana... There will be some potential for critical fire weather conditions on Tuesday on Wednesday across portions of northern Montana both ahead and behind the surface front. Fuels had moistened recently in the area but are starting to dry once again. If fuels continue to dry and winds/relative humidity continue to show worsening conditions, a 40% probability may be needed in later outlooks. ..Bentley.. 08/26/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2056 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF EASTERN OREGON AND SOUTH CENTRAL IDAHO
Mesoscale Discussion 2056 NWS Storm Prediction Center Norman OK 0332 PM CDT Sat Aug 26 2023 Areas affected...portions of eastern Oregon and south central Idaho Concerning...Severe potential...Watch unlikely Valid 262032Z - 262230Z Probability of Watch Issuance...20 percent SUMMARY...Isolated high-based strong to severe storms are possible this afternoon and evening. Damaging gusts and small hail are possible with the strongest storms. A WW is unlikely. DISCUSSION...Across the northern Intermountain west, broad southerly flow ahead of a mid-level trough was transporting monsoon moisture northward into portions of eastern OR and southern ID. At the nose of this surge, visible imagery showed new thunderstorm development ongoing across parts of far northern NV/UT into southern ID. Clear skies have allowed for strong diurnal heating and destabilization with MUCAPE of 1000-15000 J/kg observed via SPC mesoanalysis. As remaining inhibition is removed ahead of the northward lifting trough, thunderstorms should continue to develop and mature through the afternoon. Vertical shear of 30-35 kt should support some storm organization/longevity into organized multicells and perhaps transient supercell structures. Likely high based with LCLs near or exceeding 2500 m, the primary risk will be damaging outflow gusts from the more persistent storms. However, some small accumulating hail may also be possible given relatively steep mid-level lapse rates and the presence of a few longer-lived, and stronger updrafts. The primary uncertainty with regard to the severe threat this afternoon/evening is the coverage of severe storms. While a few stronger updrafts are likely to evolve, broader synoptic forcing for ascent is still relatively modest. This suggests a generally more isolated threat related to individual storm evolution through much of the day. Given this uncertainty, a new WW appears unlikely, but convective trends will be monitored. ..Lyons/Thompson.. 08/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PIH...MSO...BOI...PDT... LAT...LON 44541421 43601328 43111328 42791353 42581434 42551518 42791597 43481753 43911823 44211862 44801846 45041784 45041672 44941587 44541421 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sat Aug 26 2023 Valid 262000Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS THE SOUTHEAST MO/NORTHEAST AR VICINITY... ...SUMMARY... Occasional damaging gusts will be possible this afternoon and evening across southeast Missouri/northeast Arkansas and vicinity, with more isolated strong winds possible into the southern Appalachians and across parts of Idaho and Oregon. ...20Z Update... Overall, no changes are needed to the previous outlook. More forecast details provided below and in the appended outlook. ...Southeast MO/northeast AR area this afternoon/evening... As mentioned in recently issued MCD #2054, thunderstorms capable of producing isolated to scattered damaging winds will become increasingly possible later this afternoon across parts of southern MO/IL, northern AR, and western KY/TN. Strong heating and large PW will support a threat of at least isolated wet microbursts as these storms sag southward through the afternoon. ...Southern Appalachians into the Central Carolinas... As discussed in MCD #2055, strong heating ahead of an eastward-progressing MCV, along with typical diurnal terrain circulations should support additional thunderstorm development through this afternoon. Moderate buoyancy (1000-2000 J/kg of MLCAPE) and fairly steep low-level lapse rates should support occasional strong updrafts. As result, isolated strong to severe storms, with the potential for a few damaging downburst gusts, will be possible this afternoon and evening across the region. ...Southern ID/Eastern OR... Thunderstorm development has already be observed across the region ahead of the approaching speed max, with additional storm development still possible this afternoon/evening. Modest vertical shear could help organize updrafts, with high cloud bases and steep low-level lapse rates contributing to the potential for isolated strong/severe outflow. ..Mosier.. 08/26/2023 .PREV DISCUSSION... /ISSUED 1127 AM CDT Sat Aug 26 2023/ ...Southeast MO/northeast AR area this afternoon/evening... The persistent midlevel high continues to slowly weaken over the southern Plains, while a series of MCVs rotate around the northern and eastern periphery of the high, from KS to the southern Appalachians. The most pronounced MCV is now moving southeastward over northwest MO and will interact with the unstable warm sector this afternoon in the vicinity of southeast MO, where additional thunderstorm development is expected south of the ongoing convection near Saint Louis. Daytime heating in cloud breaks and boundary-layer dewpoints in the mid 70s will result in MLCAPE of 2500-3000 J/kg, and lapse rate profiles will also favor strong downdrafts (DCAPE of 1000-1500 J/kg). Primarily multicell clusters are expected as a result of weak vertical shear in the warm sector ahead of the MCV. Damaging outflow winds will be the main severe threat from mid-late afternoon into this evening. ...Southern ID/eastern OR this afternoon/evening... A weak mid-upper speed max is translating northward around the western periphery of the ridge from the southern Plains into the Rockies. A band of ascent and midlevel moisture, coincident with surface heating in cloud breaks, will support scattered thunderstorm development this afternoon into this evening. Typical inverted-V profiles and some modest enhancement to deep-layer vertical shear will support somewhat organized cells (and perhaps a low-end supercell) capable of producing isolated strong-severe outflow gusts. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0226 PM CDT Sat Aug 26 2023 Valid 271200Z - 281200Z Added an Elevated delineation for portions of central and northern Texas and southwest Oklahoma. Given the extreme to exceptional drought ongoing, northerly winds behind the cold front (15 gust 25 mph) may be sufficiently strong to support an increased fire weather threat despite only marginally dry relative humidity (30-35 percent). Elsewhere, the forecast remains on track with relatively benign fire weather conditions. ..Bentley.. 08/26/2023 .PREV DISCUSSION... /ISSUED 0148 AM CDT Sat Aug 26 2023/ ...Synopsis... On Sunday, the central/western US upper-level ridge will shift westward across the Four Corners. A cold front will sag southward across the Southern Plains bringing a shift to northerly flow, cooling temperatures, and rain and thunderstorm chances. While this looks like a better chance for more widespread wetting rainfall across Central Texas and southern Louisiana, more appreciable totals will likely remain somewhat localized. Due to the extremely critical nature of fuels, areas that receive very little rainfall will likely not see much change in fuel status and potential for new lightning starts. Humidity will increase with cooler temperatures behind the front. Relative humidity will be around 20 percent across central Texas ahead of the passing front, which may allow for some locally Elevated conditions. Overall, the threat is too centralized for inclusion of any Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 261729
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sat Aug 26 2023

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

Central East Pacific (EP92):
Showers and thunderstorms continue to show signs of organization in
association with a low pressure system located about 700 miles
south-southwest of the southern tip of the Baja California
Peninsula. Environmental conditions are conducive for additional
development, and a tropical depression or storm is expected to form
in the next day or so while the system moves west-northwestward or
northwestward at 10 to 15 mph over the central portion of the
tropical eastern Pacific. For additional information on this
system, including gale warnings, see High Seas Forecast issued by
the National Weather Service.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

&&

High Seas Forecasts issued by the National Weather Service
can be found under AWIPS header NFDHSFEPI, WMO header FZPN02
KWBC, and on the web at ocean.weather.gov/shtml/NFDHSFEPI.php

$$
Forecaster Kelly/Pasch

Extreme heat and drought have Selma’s Water Works and Sewer Board asking residents to curb their water use. The aim was to keep potable water flowing for all customers and to allow the city time to refill water reserves after water main breaks and use by firefighters. WSFA (Montgomery, Ala.), Aug 25, 2023

The dearth of rain and intense heat in the Jackson area has stressed the grass at the Greenwood Cemetery. The executive director explained that some graves become more visible as the grass turns brown in a rectangular shape where the grave is. Some of the graves were so old that any markers that might have existed were gone, so the drought is helpful in locating forgotten unmarked graves. WJTV TV 12 (Jackson, Miss.), Aug 25, 2023

Water customers in Elkton were asked to voluntarily conserve water because the high demand was straining the well pumps. The South Fork of the Shenandoah River was so low that one could walk across it. WHSV Online (Harrisonburg, Va.), Aug 25, 2023

Baton Rouge Water Co. and its affiliate companies serving East Baton Rouge and Ascension parishes asked more than 190,000 customers to conserve water due to high demand, intense heat and drought. Baton Rouge Advocate (La.), Aug 25, 2023

No watches are valid as of Fri Aug 25 22:26:02 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0442 PM CDT Fri Aug 25 2023 Valid 271200Z - 021200Z ...D5/Tue-D6/Wed - Texas into Louisiana... A cold front will move through the southern Plains on Sunday. In the wake of this cold front, a dry, continental airmass will move into place across much of the Plains and into parts of the Southeast. The lowest RH is expected across the regions of severe to exceptional drought across portions of Texas and Louisiana. Initially, winds behind the front will be weak on Sunday and Monday. However, on Tuesday and Wednesday, northerly/northeasterly winds will strengthen as the pressure gradient tightens between High Pressure in the central High Plains and a developing tropical system in the Gulf of Mexico. Elevated to potentially critical conditions are likely on Tuesday and Wednesday amid these strengthening post-frontal winds. ...D5/Tue - Northwest... On Tuesday, a strong mid-level trough will move across the Northwest. This system will bring the potential for thunderstorms. Any thunderstorms in western Oregon and Washington could have some concern for new lightning starts. However, less favorable fuels east of the Cascades, combined with 1+ inch PWAT values should mitigate the threat somewhat. In addition, strong winds are expected to develop as the pressure gradient tightens across the Cascades. The strongest winds will likely be in the higher terrain of the Cascades, in the Cascade gaps and in the Columbia Basin. At this time it does not appear relative humidity will be low enough, particularly where fuels are dry, to support Critical probabilities. ...D6/Wed - Northern Rockies... On Wednesday, the strong mid-level jet will move east and affect a large portion of Montana. Dry and breezy conditions are expected with some critical conditions likely. However, fuels in this area are not that favorable for large fire spread. Some drying of fuels may occur by then, and a greater threat may materialize, but for now there is enough uncertainty about fuels to preclude any Critical probabilities. ..Bentley.. 08/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2048 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WESTERN KS INTO EXTREME SOUTHERN NE
Mesoscale Discussion 2048 NWS Storm Prediction Center Norman OK 0354 PM CDT Fri Aug 25 2023 Areas affected...Western KS into extreme southern NE Concerning...Severe potential...Watch unlikely Valid 252054Z - 252300Z Probability of Watch Issuance...20 percent SUMMARY...Storms capable of hail and isolated severe gusts may increase through late afternoon. DISCUSSION...Storms are gradually increasing in coverage this afternoon from southwest NE into northwest KS, near/north of a surface low near the CO/KS state line. Thus far, the strongest storms have been to the cool side of a surface boundary across extreme southwest NE, where otherwise-weak deep-layer shear is slightly stronger due to surface northeasterly winds. Occasional strong multicells in this region may pose an isolated hail and severe gusts threat through the afternoon. Additional deepening cumulus is noted within the hot/well-mixed environment south of the surface boundary into a larger portion of western KS. As storms deepen/mature within this regime, inverted-V profiles will support a threat of isolated severe downbursts through late afternoon. Outflow consolidation may eventually result in a loosely organized cluster, but the short-term threat is expected to remain disorganized and rather isolated, rendering watch issuance unlikely. ..Dean/Thompson.. 08/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TOP...ICT...GID...LBF...DDC...GLD... LAT...LON 37900120 39040184 39940165 40510114 40219778 39559755 39019775 38399831 38039963 37980047 37900120 Read more

MD 2047 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHERN IL/IN
Mesoscale Discussion 2047 NWS Storm Prediction Center Norman OK 0325 PM CDT Fri Aug 25 2023 Areas affected...Parts of southern IL/IN Concerning...Severe potential...Watch unlikely Valid 252025Z - 252230Z Probability of Watch Issuance...20 percent SUMMARY...Isolated severe storms are possible later this afternoon into the evening, with a threat of locally damaging wind and perhaps some hail. DISCUSSION...A strong thunderstorm has recently developed across south-central IL, with an increasing cumulus field noted farther east along a surface boundary into southeast IL and southern IN. Strong to extreme buoyancy has developed within a very hot/moist environment, with MLCAPE in the 3000-4500 J/kg range per recent mesoanalyses and also noted regionally on the 18 UTC ILN sounding. While deep-layer shear is rather weak (with effective shear generally less than 25 kt), the favorable buoyancy will support a threat of isolated hail and localized downbursts with any sustained development through the afternoon. Storm coverage through the afternoon remains somewhat uncertain, with generally limited large-scale ascent and weak convergence along the boundary. With the threat expected to remain somewhat isolated, watch issuance in the short-term is considered unlikely. ..Dean/Thompson.. 08/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILN...LMK...IND...PAH...ILX...LSX... LAT...LON 39808935 39378766 39558605 39338490 38848482 38178595 38078740 38458936 38918970 39128986 39808935 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Fri Aug 25 2023 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL ILLINOIS INTO PARTS OF INDIANA... ...SUMMARY... Isolated to scattered thunderstorms associated with strong wind gusts and marginally severe hail are possible this afternoon and evening from Kansas to Virginia and across Upper Michigan, with the somewhat greater threat focused from central Illinois into southwest Indiana. Only minor changes were made at 20Z, including adjusting low probabilities farther across eastern Upper MI ahead of a frontal wave, and expanding a low wind threat into more of southeast KS and southern MO where a few storms have formed within the hot air mass. A small 2% tornado area has also been added for the area from far southern OH into a small part of northeast KY. Here, objective analysis indicates 0-1 SRH near 100 m2/s2, which may aid rotation potential in the area north of the primary KY MCS. ..Jewell.. 08/25/2023 .PREV DISCUSSION... /ISSUED 1127 AM CDT Fri Aug 25 2023/ ...IL/IN this afternoon/evening... An outflow-reinforced front extends from WV/southern OH to central IL, while a second outflow surge is moving southeastward into northern MO and west central IL. The merger zone of these two boundaries appears to be the more probable area for thunderstorm development this afternoon into IL, along the north gradient of the 78-80 F boundary-layer dewpoints. Modified 12z soundings and short-term model forecasts suggest that MLCAPE could exceed 4000 J/kg with weakening convective inhibition, while steep midlevel lapse rates will also result in large DCAPE (> 1200 J/kg). With most of the vertical shear (25-30 kt magnitudes) concentrated in the lowest 3 km, the primary convective mode is expected to be multicell clusters and perhaps a relatively short-lived supercell or two capable of producing damaging outflow winds. ...Eastern KY to VA through this evening... The remnants of overnight convection persist from WV into eastern KY. The warmest surface temperatures and higher dewpoints to the west across KY suggest that the preferred development of new storms will also be toward the west and southwest this afternoon, where isolated strong downburst winds will be possible. Farther east into VA, somewhat lesser boundary-layer moisture (mixed mainly into the mid-upper 60s) and lesser midlevel lapse rates will support weaker buoyancy (MLCAPE in the 1500-2000 J/kg range) compared to KY/southern OH. Despite the early passage of the convectively-enhanced midlevel trough, 25-30 kt midlevel flow will linger over VA/MD this afternoon. Thunderstorm development will be possible this afternoon along a weak lee trough, as well as any persistent differential heating zones (mainly across southwest VA) and along a cold front moving southeastward from PA. The overall threat for damaging winds with downbursts still appears to be best categorized as MRGL, so will maintain the 5% wind probabilities. ...Northeast MN into Upper MI this afternoon/evening... A pronounced midlevel shortwave trough is moving east-southeastward over the MN Arrowhead/Lake Superior. A narrow zone of destabilization coincident with a band of ascent will support at least widely thunderstorms through the afternoon. Though buoyancy will be modest (MLCAPE of 500-1000 J/kg), long hodographs will support organized/supercell storms capable of producing isolated wind damage and marginally severe hail. ...Eastern CO to KS/NE border this afternoon/evening... As the surface warms with daytime heating, high-based thunderstorm development is expected along a slow-moving front in KS and in a zone of low-level upslope flow in CO by mid-late afternoon. Vertical shear will be relatively weak, but deep inverted-V profiles with large DCAPE will support the potential for strong to isolated severe outflow gusts this afternoon into this evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0205 PM CDT Fri Aug 25 2023 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 08/25/2023 .PREV DISCUSSION... /ISSUED 0116 AM CDT Fri Aug 25 2023/ ...Synopsis... Strong upper-level ridging across the central/western US will generally keep winds light across much of the CONUS where fuels are the driest on Saturday. A weak disturbance moving across northern Montana may lead to locally breezy and dry conditions but relative humidity looks to stay largely above 20 percent. Hot and dry conditions will continue across portions of Texas and Louisiana where well below normal rainfall has led to extreme to exceptional drought and extremely critically dry fuels. Winds within this region will remain light and preclude the need to include any areas at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 251747
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Fri Aug 25 2023

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

Central East Pacific (EP92):
Showers and thunderstorms are gradually becoming better organized in
association with a low pressure area located about 800 miles
south-southwest of the southern tip of the Baja California
Peninsula. Environmental conditions are conducive for additional
development, and a tropical depression is expected to form during
the next few days while it moves west-northwestward at 10 to 15 mph
over the central portion of the tropical eastern Pacific.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 7 days...high...90 percent.

South of Southwestern Mexico (EP91):
A trough of low pressure located a few hundred miles south of the
southern and southwestern coast of Mexico continues to produce
disorganized shower and thunderstorm activity. Environmental
conditions appear marginally conducive for some slow development of
this system, and a tropical depression could form during the next
few days while it moves slowly northwestward or northward toward
southwestern Mexico. Interests in southwestern Mexico should
monitor the progress of this system.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Blake

Landscapers in the Shenandoah Valley were mowing less due to drought and were doing other jobs like mulching to keep busy. WHSV Online (Harrisonburg, Va.), Aug 24, 2023

After several seasons of low water levels at Crescent Lake, the Crescent Ranger District staff intends to reevaluate the project design in light of present and future lake conditions to offer a good design for such conditions. The lake was in severe drought and may need several years of well above average snowfall and precipitation to return to normal levels. KTVZ-TV NewsChannel 21 (Redmond, Ore.), Aug 23, 2023

Insects in East Texas were stressed by the dry conditions. Ants and other pests were making their way into homes in search of moisture. KYTX CBS19 (Tyler, Texas), Aug 24, 2023

A bait shop owner near Lake Corpus Christi reported that his business was suffering as drought lowered lake levels, causing certain boat ramps to close. Fortunately, Tropical Storm Harold just brought rain that refilled the lake, so business should rebound. KRISTV NBC 6 Corpus Christi (Texas), Aug 23, 2023