SPC Aug 28, 2023 2000 UTC Day 1 Convective Outlook

1 year 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0245 PM CDT Mon Aug 28 2023 Valid 282000Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON ACROSS PORTIONS OF THE SOUTHEAST... ...SUMMARY... Isolated storms capable of strong and gusty winds are possible across the Southeast this afternoon. ...20Z Update... ...Southeast... 18Z soundings sampled a moist, moderately buoyant, and weakly sheared environment across the region. This matches the overall expectation outlined in the previous outlook (appended below), with a predominantly disorganized multicellular storm mode anticipated. Isolated water-loaded downbursts remain possible, particularly from southern MS and across much of AL where the highest storm coverage is anticipated. ...Central/Southern High Plains... Convective initiation has already occurred across the high terrain, with southeastward motion still expected to take these storms into the High Plains. Mesoanalysis estimated effective bulk shear is already 20 to 25 kt across the region, with some additional increase anticipated throughout the afternoon. As such, some organization is possible, with an attendant threat for a strong gust or two. Overall coverage is still expected to remain too low for an outlook area. ..Mosier.. 08/28/2023 .PREV DISCUSSION... /ISSUED 1126 AM CDT Mon Aug 28 2023/ ...Southeast this afternoon... A weak midlevel trough persists from the northern Gulf of Mexico to the southern Appalachians with multiple embedded vorticity maxima. Vertical shear is very weak across the Southeast, and thermodynamic profiles are less favorable for strong downdrafts compared to previous days. Thus, scattered pulse-type storms are expected this afternoon along a combination of a stalled synoptic front, weak differential heating zones and local sea breeze circulations. The wind-damage threat appears to be on the lower margins for an outlook area, but will maintain the 5% area for the possibility of isolated downbursts. ...Central/southern High Plains this afternoon/evening... Similar to yesterday, a few storm clusters will form this afternoon and move south-southeastward from southeast WY across eastern CO into eastern NM through this evening. Effective bulk shear of 25-30 kt will support semi-organized storms, a few of which could produce gusty outflow winds and small hail. However, the storms will be relatively low topped for late summer and the severe threat appears too marginal to add an outlook area. ...Tropical cyclone Idalia and FL... Tropical storm Idalia is expected to become a hurricane later today into tonight while moving northward toward the southeast Gulf of Mexico (please refer to latest NHC advisories for additional information). The stronger wind profiles and associated supercell threat will likely be delayed in FL until Tuesday during the day, so will not add any tornado probabilities in this update. Read more

SPC Day 2 Fire Weather Outlook

1 year 11 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook CORR 1 NWS Storm Prediction Center Norman OK 0245 PM CDT Mon Aug 28 2023 Valid 291200Z - 301200Z CORRECTED FOR INCORRECT GRAPHIC An Elevated fire-weather area has been added for southwest Idaho and vicinity where winds of 25 to 30 mph and single digit relative humidity are expected. Much of the Great Basin fuels are too moist to support fire spread. However, across southwest Idaho, there was less recent rainfall and therefore, fuels may be at least somewhat susceptible to large fire, especially given the very windy and dry conditions anticipated. No changes were made elsewhere. See previous discussion below. ..Bentley.. 08/28/2023 .PREV DISCUSSION... /ISSUED 0202 AM CDT Mon Aug 28 2023/ ...Synopsis... On Tuesday, a trough will bring an increase in shower and thunderstorm activity across the Pacific Northwest, along with pre-frontal breezy conditions across portions Montana. Across the Southern Plains pressure gradients will increase between the Southwest high and a tropical system impacting the Gulf of Mexico, leading to an increase in surface winds. ...North-Central Texas and Southern Oklahoma... Winds speeds will increase to around 10-15 mph Tuesday afternoon across portions of north-central Texas and southern Oklahoma amid afternoon relative humidity reductions to around 20-30 percent. Fuels within this region remain critically dry, as very little rain has fallen across this region in the last 7 days and prolonged drought has led to drought stress. Given that relative humidity looks to largely stay above Critical thresholds, an Elevated delineation should cover the larger threat well. ...North-Central Montana... Pre-frontal winds will increase to around 15-20 mph amid relative humidity reductions to around 20-25 percent across north-central Montana Tuesday afternoon. Fuels within this region have experienced some drying due to lack of recent rainfall. However, fuels largely remain at or below average precluding the need for Critical highlights and as such an Elevated delineation was most appropriate. ...Dry Thunderstorms... An increase in shower and thunderstorm chances is possible across the Pacific Northwest on Tuesday. Precipitable water values across eastern Washington, northern Idaho, and western Montana will range around 0.50-1.00" with potential for fast storm motions. This will likely result in a mix of wet and dry thunderstorm activity. Ensemble data from the HREF indicates the more appreciable rainfall may be more likely across northern Idaho/western Montana with amounts generally up to and less than 0.10" across eastern Washington across the Cascades and central Columbia Basin. This will need to be monitored for inclusion of isolated dry thunderstorms. For now, confidence remains low in exactly which areas will remain mostly dry. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Eastern North Pacific Tropical Weather Outlook

1 year 11 months ago

000
ABPZ20 KNHC 281740
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Mon Aug 28 2023

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

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

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

$$
Forecaster Bucci
NHC Webmaster

SPC Aug 28, 2023 1730 UTC Day 2 Convective Outlook

1 year 11 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Mon Aug 28 2023 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHWEST/WEST-CENTRAL FLORIDA PENINSULA... ...SUMMARY... The potential for a few tornadoes should gradually increase along/near parts of the Florida Gulf Coast and into north Florida through Tuesday night as Tropical Cyclone Idalia approaches. ...Florida into Southeast Georgia... Latest forecast for TC Idalia centers the system northwest of western Cuba early Tuesday morning, with northeastward/north-northeastward motion taking the storm to just off northwestern FL Peninsula by 12Z Wednesday morning. Strong low/mid-level flow associated with this system will gradually spread northward across the FL Peninsula throughout the day, with the strongest winds expected along the western coast after 00Z. Rain bands will likely begin moving across the peninsula during the early afternoon, with a generally northeastward storm motion anticipated. Lapse rates will be poor, but the moist airmass across the region will still support moderate buoyancy and the potential for a few strong updrafts. The most significant increases in low-level shear are not expected under after 00Z, so the severe-gust and tornado potential with these multicellular bands will be low, but not zero. After 00Z through the remainder of the period, strengthening low to mid-level flow will result in a gradually increasing tornado potential, particular along the west-central and northwest portions of the FL Peninsula. TC tornado climatology shows a notable preference for tornadoes between 200-300 km northeast of the center for northeastward progressing major hurricanes. This matches well with the most favorable environmental conditions for tornadogenesis in this case, which are along the northwest/west-central FL coast from 06Z-12Z. ...Interior Pacific Northwest into the Northern Rockies... A negatively tilted shortwave trough is forecast to progress across the Pacific Northwest on Tuesday. Moderate mid-level flow and moisture will spread eastward ahead of this wave across ID and into western MT. Resulting combination of a deeply mixed boundary layer, increasing mid-level moisture, and strengthening ascent is expected to result in afternoon/evening thunderstorm development. 20 to 30 kt of effective shear will help organize some updrafts, with high cloud bases and steep low-level lapse rates supporting the potential for strong outflow. An instance or two of hail is possible as well. ...Great Lakes/OH Valley... A cold front is forecast move southeastward across the Great Lakes and parts of the Midwest/OH Valley, in tandem with an eastward-moving upper trough. Dewpoints will likely be in the upper 50s and low 60s from IL into IN and MI ahead of this front, but mid-level temperatures will be relatively warm, limiting buoyancy and updraft strength/duration. Damaging gusts would be possible with any deep, sustained updrafts, but the overall probability of occurrence currently appears low. ...Appalachians... Scattered thunderstorms should develop across parts of the southern/central Appalachians Tuesday afternoon, as modest ascent associated with an upper trough moving Quebec and the Upper Great Lakes/OH Valley glances the region. Modest deep-layer vertical shear is anticipated amid the southwesterly mid-level flow stretching across the region, supporting potential updraft organization. Even so, poor lapse rates should limit instability and overall updraft strength. A generally multicellular, outflow-dominant storm mode is anticipated, and the potential for a damaging gust or two exists within any bowing segments. However, overall severe coverage is expected to remain too low to include severe probabilities. ..Mosier.. 08/28/2023 Read more

Grapes ripened faster in Rochester, Minnesota

1 year 11 months ago
The wine grapes in southeastern Minnesota have seen a lot of dry days this growing season. The younger vines have been irrigated since their root systems are not as well developed as older vines. Some of the grapes have ripened faster this year. KIMT 3 (Rochester, Minn.), Aug 18, 2023

SPC Day 3-8 Fire Weather Outlook

1 year 11 months ago
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0454 PM CDT Sun Aug 27 2023 Valid 291200Z - 041200Z ...D3/Tue - D4/Wed - Southern Plains... Dry and breezy conditions will develop in the northerly flow between the high pressure in the High Plains and the tropical system in the Gulf of Mexico. Thunderstorms Saturday and Sunday likely provided wetting rains for some locations, but others will still have exceptionally dry fuels. ......D3/Tue - Montana... There will be some potential for critical fire weather conditions on Tuesday across portions of northern Montana. Pre-frontal winds are expected to be strongest across portions of north-central Montana where minimal precipitation fell last week. Therefore, 40 percent probabilities have been added for the increasing threat for elevated to critical fire weather conditions across north-central Montana on Tuesday. ...D3/Tue - D4/Wed - Northwest... A negatively tilted mid-level trough will move across the Pacific Northwest on Tuesday. This will bring numerous thunderstorms, particularly across Washington. 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. Nonetheless, no dry thunderstorm probabilities have been added due to the questions regarding storm wetness and only marginally dry fuels east of the Cascades where storms may be more dry. As this trough advances east, some breezy conditions are expected in the Columbia Basin. 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. At this time, no 40 percent probabilities have been added as relative humidity is forecast to stay 30%+ where fuel are critically dry. ..Bentley.. 08/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC MD 2057

1 year 11 months ago
MD 2057 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHERN MS AND LA INTO FAR EAST TX
Mesoscale Discussion 2057 NWS Storm Prediction Center Norman OK 0345 PM CDT Sun Aug 27 2023 Areas affected...portions of southern MS and LA into far east TX Concerning...Severe potential...Watch unlikely Valid 272045Z - 272245Z Probability of Watch Issuance...5 percent SUMMARY...Scattered thunderstorms with isolated downburst winds are possible this afternoon/early evening. DISCUSSION...Across portions of the lower MS Valley and central Gulf Coast, afternoon thunderstorms were observed developing along a frontal boundary/remnant outflow. Strong diurnal heating has eroded inhibition with 1500-2000 J/kg of MLCAPE supporting occasional stronger updrafts. Deep-layer vertical shear across much of the region is exceedingly weak at generally less than 10-15 kt. This will support multi-cellular, pulse convection as the primary storm mode. Weak surface flow is also not expected to support much cold pool propagation and storm conglomeration seems unlikely. Thus, the primary severe risk will be tied to individual pulse downdrafts as storms collapse. Greater than 1000 J/kg of DCAPE and steep low-level lapse rates from very warm temperatures may support stronger outflow winds with sporadic damaging gusts. With little in the way of storm organization or longevity expected, a WW appears very unlikely. ..Lyons/Thompson.. 08/27/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MOB...JAN...LIX...LCH...SHV...HGX...FWD... LAT...LON 30928898 31268945 31629039 31919184 32109304 32259432 32229507 31889558 31469563 31109535 30429450 30209361 29989193 29839020 30248937 30418909 30928898 Read more

Tropical Storm Irwin Forecast Discussion Number 4

1 year 11 months ago
Issued at 1100 AM HST Sun Aug 27 2023 791 WTPZ45 KNHC 272042 TCDEP5 Tropical Storm Irwin Discussion Number 4 NWS National Hurricane Center Miami FL EP102023 1100 AM HST Sun Aug 27 2023 The cloud pattern has changed little in appearance this morning. The center of circulation remains displaced to the north of a shapeless deep convective mass, likely due to a combination of modest northeasterly shear and dry mid-tropospheric air intruding from the northwest. A scatterometer pass over the eastern half of the cyclone indicated southerly winds of 35-37 kt well removed from the center, and the initial intensity is held at 35 kt for this advisory. Irwin should be able to produce sufficient deep convection, particularly in the eastern semicircle, along with intermittent bursts near the center, thereby maintaining its tropical storm status in the short term. Subsequently, the relatively large circulation should take some time to spin down similar to what the global and regional guidance suggests. Decreasing SSTs and a dry, stable marine layer air mass is expected to cause the cyclone to weaken to a depression in a few days and degenerate into a remnant low toward the end of the forecast period. Using surface center fixes from visible and recent microwave imagery, along with the previously mentioned partial METOP-B/C scatterometer wind overpasses, gives an estimated initial motion of west-northwestward, or 295/9 kt. A subtropical high pressure anchored to the north of the cyclone should maintain a generally west-northwestward to westward heading through day 5. Along-track inconsistency in the models continues to complicate the forecast track solution. The best approach in this case, however, is to side with a compromise of the best-performing HCCA and TVCE consensus guidance, and is the basis of the official forecast. FORECAST POSITIONS AND MAX WINDS INIT 27/2100Z 17.2N 121.3W 35 KT 40 MPH 12H 28/0600Z 17.7N 122.5W 40 KT 45 MPH 24H 28/1800Z 18.4N 124.6W 40 KT 45 MPH 36H 29/0600Z 18.6N 127.2W 35 KT 40 MPH 48H 29/1800Z 18.6N 130.0W 35 KT 40 MPH 60H 30/0600Z 18.4N 132.7W 35 KT 40 MPH 72H 30/1800Z 18.4N 135.2W 30 KT 35 MPH 96H 31/1800Z 18.8N 138.9W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 01/1800Z 19.1N 141.4W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Roberts
NHC Webmaster

Tropical Storm Irwin Public Advisory Number 4

1 year 11 months ago
Issued at 1100 AM HST Sun Aug 27 2023 000 WTPZ35 KNHC 272041 TCPEP5 BULLETIN Tropical Storm Irwin Advisory Number 4 NWS National Hurricane Center Miami FL EP102023 1100 AM HST Sun Aug 27 2023 ...IRWIN MOVING WEST-NORTHWESTWARD OVER THE TROPICAL EASTERN PACIFIC WITH NO CHANGE IN STRENGTH... SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION ----------------------------------------------- LOCATION...17.2N 121.3W ABOUT 835 MI...1345 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...WNW OR 295 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...998 MB...29.47 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM HST (2100 UTC), the center of Tropical Storm Irwin was located near latitude 17.2 North, longitude 121.3 West. Irwin is moving toward the west-northwest near 10 mph (17 km/h). A turn toward the west is anticipated on Monday. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Some strengthening is expected in the short term. Weakening is forecast to begin Monday night. Tropical-storm-force winds extend outward up to 60 miles (95 km) from the center. The estimated minimum central pressure is 998 mb (29.47 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 500 PM HST. $$ Forecaster Roberts
NHC Webmaster

Tropical Storm Irwin Wind Speed Probabilities Number 4

1 year 11 months ago
Issued at 2100 UTC SUN AUG 27 2023 000 FOPZ15 KNHC 272041 PWSEP5 TROPICAL STORM IRWIN WIND SPEED PROBABILITIES NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102023 2100 UTC SUN AUG 27 2023 AT 2100Z THE CENTER OF TROPICAL STORM IRWIN WAS LOCATED NEAR LATITUDE 17.2 NORTH...LONGITUDE 121.3 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 35 KTS...40 MPH...65 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 SUN 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 SUN 06Z MON 18Z MON 06Z TUE 18Z TUE 18Z WED 18Z THU PERIODS TO TO TO TO TO TO TO 06Z MON 18Z MON 06Z TUE 18Z TUE 18Z WED 18Z THU 18Z FRI FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 125W 34 X 1( 1) 2( 3) 1( 4) X( 4) X( 4) X( 4) 20N 130W 34 X X( X) 1( 1) 9(10) 1(11) X(11) X(11) 20N 135W 34 X X( X) X( X) X( X) 6( 6) 1( 7) X( 7) 20N 140W 34 X X( X) X( X) X( X) X( X) 2( 2) 2( 4) $$ FORECASTER ROBERTS
NHC Webmaster

Tropical Storm Irwin Forecast Advisory Number 4

1 year 11 months ago
Issued at 2100 UTC SUN AUG 27 2023 000 WTPZ25 KNHC 272040 TCMEP5 TROPICAL STORM IRWIN FORECAST/ADVISORY NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102023 2100 UTC SUN AUG 27 2023 NOTICE... LAND-BASED TROPICAL CYCLONE WATCHES AND WARNINGS ARE NO LONGER INCLUDED IN THE TROPICAL CYCLONE FORECAST/ADVISORY...(TCM). CURRENT LAND-BASED COASTAL WATCHES AND WARNINGS CAN BE FOUND IN THE MOST RECENTLY ISSUED TROPICAL CYCLONE PUBLIC ADVISORY...(TCP). TROPICAL STORM CENTER LOCATED NEAR 17.2N 121.3W AT 27/2100Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 295 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 998 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 50NE 20SE 0SW 0NW. 12 FT SEAS.. 30NE 0SE 0SW 30NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 17.2N 121.3W AT 27/2100Z AT 27/1800Z CENTER WAS LOCATED NEAR 17.0N 120.9W FORECAST VALID 28/0600Z 17.7N 122.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 20SE 0SW 40NW. FORECAST VALID 28/1800Z 18.4N 124.6W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 20SE 0SW 40NW. FORECAST VALID 29/0600Z 18.6N 127.2W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 60NE 10SE 10SW 60NW. FORECAST VALID 29/1800Z 18.6N 130.0W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 60NE 10SE 10SW 60NW. FORECAST VALID 30/0600Z 18.4N 132.7W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 50NE 10SE 10SW 60NW. FORECAST VALID 30/1800Z 18.4N 135.2W MAX WIND 30 KT...GUSTS 40 KT. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 31/1800Z 18.8N 138.9W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. OUTLOOK VALID 01/1800Z 19.1N 141.4W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.2N 121.3W NEXT ADVISORY AT 28/0300Z $$ FORECASTER ROBERTS
NHC Webmaster

SPC Aug 27, 2023 2000 UTC Day 1 Convective Outlook

1 year 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Sun Aug 27 2023 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM CENTRAL TX INTO THE CAROLINAS... ...SUMMARY... Thunderstorms capable of locally damaging winds are possible mainly this afternoon and early evening spanning parts of Texas to the Carolinas. ...20Z Update... Overall forecast remains unchanged. Scattered thunderstorms will continue throughout the afternoon into this evening from central TX across the Southeast into the Carolinas. Vertical shear is weak, but steep low-level lapse rates and ample low-level moisture could still support isolated damaging wind gusts. Scattered thunderstorms continue to develop from southeast WY into eastern CO/NM. MLCAPE is generally 500 to 1000 J/kg amid 20 to 30 kt of effective bulk shear, contributing to the potential for a few storms capable of producing hail and/or damaging gusts. Coverage is still expected to be too low to introduce any wind/hail areas. ..Mosier.. 08/27/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sun Aug 27 2023/ ...TX to the Carolinas this afternoon/early evening... A cold front will continue to sag slowly southward from central TX to the Ark-La-Miss and the Carolinas. The effective front is marked by outflow from northwest AL across central MS to northern LA, in association with an MCV that is moving south-southeastward over northwest MS. Away from ongoing convection/cloud debris, strong surface heating will drive MLCAPE values of 1500-3000 J/kg with minimal convective inhibition, which will allow scattered thunderstorm development along the front and mesoscale boundaries/terrain circulations. Steep low-level lapse rates and DCAPE of 750-1250 J/kg will support the potential for isolated wind damage with downbursts, in an environment of weak vertical shear. ...Central/southern High Plains this afternoon/evening... Residual low-level moisture and weak upslope flow will support scattered thunderstorms this afternoon from southeast WY to eastern CO and eastern NM. Buoyancy will remain rather modest (MLCAPE of 1000-1500 J/kg) and there will be sufficient vertical shear for semi-organized storms with the potential for isolated strong gusts and some hail. However, the overall severe potential appears to be too low to warrant the addition of wind/hail outlook areas. Read more

SPC Aug 27, 2023 2000 UTC Day 1 Convective Outlook

1 year 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Sun Aug 27 2023 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM CENTRAL TX INTO THE CAROLINAS... ...SUMMARY... Thunderstorms capable of locally damaging winds are possible mainly this afternoon and early evening spanning parts of Texas to the Carolinas. ...20Z Update... Overall forecast remains unchanged. Scattered thunderstorms will continue throughout the afternoon into this evening from central TX across the Southeast into the Carolinas. Vertical shear is weak, but steep low-level lapse rates and ample low-level moisture could still support isolated damaging wind gusts. Scattered thunderstorms continue to develop from southeast WY into eastern CO/NM. MLCAPE is generally 500 to 1000 J/kg amid 20 to 30 kt of effective bulk shear, contributing to the potential for a few storms capable of producing hail and/or damaging gusts. Coverage is still expected to be too low to introduce any wind/hail areas. ..Mosier.. 08/27/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sun Aug 27 2023/ ...TX to the Carolinas this afternoon/early evening... A cold front will continue to sag slowly southward from central TX to the Ark-La-Miss and the Carolinas. The effective front is marked by outflow from northwest AL across central MS to northern LA, in association with an MCV that is moving south-southeastward over northwest MS. Away from ongoing convection/cloud debris, strong surface heating will drive MLCAPE values of 1500-3000 J/kg with minimal convective inhibition, which will allow scattered thunderstorm development along the front and mesoscale boundaries/terrain circulations. Steep low-level lapse rates and DCAPE of 750-1250 J/kg will support the potential for isolated wind damage with downbursts, in an environment of weak vertical shear. ...Central/southern High Plains this afternoon/evening... Residual low-level moisture and weak upslope flow will support scattered thunderstorms this afternoon from southeast WY to eastern CO and eastern NM. Buoyancy will remain rather modest (MLCAPE of 1000-1500 J/kg) and there will be sufficient vertical shear for semi-organized storms with the potential for isolated strong gusts and some hail. However, the overall severe potential appears to be too low to warrant the addition of wind/hail outlook areas. Read more

SPC Day 2 Fire Weather Outlook

1 year 11 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Sun Aug 27 2023 Valid 281200Z - 291200Z No changes were made to the Elevated area on Monday across Texas and southern Oklahoma. Some windy conditions are expected through the Cascade gaps tomorrow afternoon and evening. However, this is expected to be accompanied by a marine push which should keep relative humidity high enough to avoid more significant fire weather concerns. ..Bentley.. 08/27/2023 .PREV DISCUSSION... /ISSUED 1225 AM CDT Sun Aug 27 2023/ ...Synopsis... On Monday, post frontal northerly winds will filter in a dry continental air mass across southern Oklahoma/north-central Texas. Sustained winds around 10-15 mph will overlap relative humidity around 20-25 percent. Fuels within this region are critically dry, though there is a chance for wetting rainfall with shower and thunderstorm activity on Sunday. Widespread rainfall heavy enough to alter status of fuels is unlikely, which will keep Elevated to near Critical conditions possible. An Elevated delineation was maintained for now and will be adjusted as needed based on rainfall trends on Sunday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Eastern North Pacific Tropical Weather Outlook

1 year 11 months ago

000
ABPZ20 KNHC 271706
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun Aug 27 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Depression Ten-E, located several hundred miles southwest of the
southern tip of Baja California peninsula.

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

&&

Public Advisories on Tropical Depression Ten-E are issued under WMO
header WTPZ35 KNHC and under AWIPS header MIATCPEP5.
Forecast/Advisories on Tropical Depression Ten-E are issued under
WMO header WTPZ25 KNHC and under AWIPS header MIATCMEP5.

$$
Forecaster Kelly
NHC Webmaster