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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Thu Aug 17 2023 Valid 172000Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL/SOUTHERN GREAT LAKES REGION AND ALSO PARTS OF THE NORTHEAST... ...SUMMARY... Isolated strong to severe thunderstorms remain possible late this afternoon across parts of the central/southern Great Lakes region, and later tonight over parts of the Northeast. ...IL/IN/OH/MI... The Marginal Risk has been trimmed slightly from the west across northeast IL, to account for the progression of the cold front. Otherwise, the previous outlook reasoning remains valid. A few strong storms may develop as the cold front moves eastward, with a threat of isolated hail and damaging winds. See the previous discussion below for more information. ...PA/NJ/NY... The 5% wind and 2% tornado probabilities have been expanded slightly eastward, to account for the potential progression of overnight convection through the end of the period. Wind profiles will be favorable for organized convection in the vicinity of a warm front, as storms develop late tonight across eastern PA. The magnitude of the severe threat remains uncertain due to limited instability, but locally damaging winds and perhaps a tornado will be possible as storms move eastward toward southern New England by Friday morning. ..Dean.. 08/17/2023 .PREV DISCUSSION... /ISSUED 1109 AM CDT Thu Aug 17 2023/ ...IN/OH/Lower MI... A large and progressive upper trough is moving across the central Great Lakes region today, with an associated surface cold front digging southeastward across northern IL. A pre-frontal band of thunderstorms extends from central IL into lower MI, and is situated along the axis of the low-level jet. This precipitation will significantly limit daytime heating for much of the day ahead of the front and preclude a more organized severe threat. Nevertheless, a consensus of 12z CAM solutions suggest a narrow corridor of heating in the wake of this pre-frontal activity later this afternoon over parts of IN/OH. Sufficient instability and favorable deep-layer shear will support a few organized storms, with a risk of strong winds and hail in the most intense cells. This threat should end around sunset. ...PA/NJ/NY... Later tonight, large scale forcing associated with the approaching upper trough will spread into eastern PA and vicinity. Greater low-level moisture will be in place across this region as dewpoints in the upper 60s advect northward. Diurnal cooling/de-coupling will likely limit the severe threat. But there is some chance of an occasional rotating storm during the late evening or overnight, capable of gusty winds or perhaps a brief tornado. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0209 PM CDT Thu Aug 17 2023 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR COLUMBIA BASIN... ...CRITICAL FIRE WEATHER AREA FOR PARTS OF NORTHERN MONTANA... No changes to the ongoing forecast. ..Wendt.. 08/17/2023 .PREV DISCUSSION... /ISSUED 0149 AM CDT Thu Aug 17 2023/ ...Synopsis... A mid-level trough over the Pacific Northwest is forecast to intensify and shift eastward, suppressing the strong ridge centered over the southern Plains. At the surface, a cyclone in southern Canada will deepen, enhancing westerly winds along the international border. Very hot and dry conditions are expected over parts of the Plains and Intermountain West. Dry and breezy west winds are expected over parts of the Northwest and northern Rockies with widespread elevated to critical fire-weather conditions likely. ...Northwest and northern Rockies... As the Pacific trough moves inland it is forecast to strengthen, resulting in moderate mid-level westerly flow over much of the Northwest. At the same time, the surface cyclone over southern Alberta should deepen, enhancing low-level flow in its wake. Downslope winds of 20-25 mph are likely in the lee of the Cascades and across the western Columbia Basin. Warm temperatures will also support low afternoon RH of 15-20% from eastern WA to central MT. With area fuels rather dry, widespread critical fire-weather conditions are likely. Dry and windy conditions will extend eastward across the northern Rockies as the surface low approaches later in the day. While slightly cooler in the wake of a prior cold front, strong surface winds of 20-30 mph are expected over parts of northern/western MT. With afternoon RH values of 20-25% critical conditions still appear likely. As westerly winds increase, the monsoon moisture that has lingered over northern CA and southern OR will be shunted eastward. Isolated showers and thunderstorms are possible over parts of central and northeast OR into western ID/MT. Model soundings show relatively high PWAT values near 1 inch, but fast storm motions greater than 30 mph. Lightning strikes are possible outside of the wetter cores with these storms as they move over areas of dry fuels. However, storm coverage and the potential for some wetting rain cast considerable uncertainty on the need for IsoDryT highlights. ...Texas... As the ridge continues to build, extremely hot temperatures are forecast to redevelop over parts of southern and central TX. Highs over 100F along with exceptionally dry fuels will be the primary catalyst for locally elevated fire-weather activity. Southerly surface winds, while not robust, may occasionally reach 10-15 mph further increasing concerns for locally elevated fire-weather conditions over central parts of the state. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 171753
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Thu Aug 17 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Hilary, located several hundred miles south-southeast of the
southern tip of Baja California peninsula.

South of Southern Mexico:
A broad area of low pressure could form offshore of the coast of
southern Mexico during the early or middle part of next week. Some
gradual development of this system is possible thereafter while it
moves slowly west-northwestward or northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Bucci

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Thu Aug 17 2023 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NEW ENGLAND AND ARIZONA... ...SUMMARY... Isolated severe thunderstorms with a risk for damaging gusts and perhaps a tornado or two will be possible during the day across portions of New England on Friday. Storms capable of isolated severe gusts will also be possible across parts of Arizona. ...Synopsis... A seasonably deep/strong upper-level trough will move across the Northeast and Mid Atlantic regions on Friday. An associated surface low will move eastward across Quebec, as a trailing cold front moves from the upper Great Lakes into New England through the day. Farther west, a mid/upper-level low will remain nearly stationary off of the California coast. A mid/upper-level shortwave trough and associated surface low will move across the Canadian Prairies, as an attendant cold front moves into the northern Plains. ...Northeast... Multiple rounds of convection are possible across parts of the Northeast/New England on Friday. The initial morning to early afternoon round may be capable of locally damaging gusts and perhaps a tornado or two, with a more isolated threat later Friday afternoon along/ahead of the cold front. One or more storm clusters will likely be ongoing Friday morning somewhere from northern NY into southern New England. Strong deep-layer flow associated with the approaching upper trough will support sufficient effective shear for organized convective elements within these clusters. The strongest buoyancy (with MLCAPE generally 500-1000 J/kg during the morning) is expected near/south of a northward-advancing warm front across southern New England, with weaker instability extending northward into parts of VT/NH. The morning threat will likely be maximized near/south of the warm front, where line-embedded supercells and/or shorter-lived mesovortices will support potential for locally damaging gusts and perhaps a tornado or two, within an environment of favorable low-level shear/SRH. Depending on the extent of heating/destabilization that can occur across southern New England prior to storm arrival, higher severe probabilities may eventually be needed. In the wake of early-day convection, redevelopment along/ahead of the cold front will be possible during the afternoon. Coverage and intensity of convection associated with the cold front remain uncertain, with storms potentially struggling to mature due to generally weak instability and a midlevel dry slot overspreading the region. However, a few strong to locally severe storms will be possible within this frontal regime, with a threat of locally damaging gusts and small to marginally severe hail. ...Arizona... Scattered to numerous thunderstorms are expected Friday from AZ into southern NV/UT, as moisture continues to increase east of the nearly stationary upper-level trough off of the CA coast. Modest southerly midlevel flow will support the potential for loosely organized, north to northwesterly moving clusters during the afternoon and evening. Localized severe gusts will be possible where somewhat stronger preconvective heating/destabilization occurs, which currently appears most likely across the lower elevations of southern/central AZ. Small hail and gusty winds will also be possible into northern AZ, though coverage of any severe threat remains more uncertain across this area. ...Montana... Widely scattered high-based convection is expected across parts of MT Friday afternoon and evening. Hot, deeply mixed boundary layers will support the potential for localized severe gusts, though the threat appears too disorganized and unfocused for severe-wind probabilities at this time. ..Dean.. 08/17/2023 Read more

Wisconsin has had about 250 more wildfires than usual since the start of the year due to persistent drought, according to the Wisconsin Department of Natural Resources. There have been 871 fires that have consumed nearly 4,400 acres to date, compared to the 10-year average of 614 fires and roughly 1,800 acres burned. Wisconsin Public Radio (Madison), Aug 11, 2023

Water was not flowing at Headwaters at the Comal. Water that used to be flowing and clear had become cloudy and filled with algae as extreme heat and drought depleted the flow. Fewer birds, butterflies and dragonflies can be found at the Headwaters riverside grassland ecosystem. Native grasses and plants were brown and dry. At Landa Lake, the Landa Lake Boathouse was closed early for the season due to low water levels. Launching boats was not safe. A burn ban was reinstated in early July and remained in effect. Open flames were prohibited. The extreme fire risk led the county to issue a disaster declaration due to the ongoing heat wave and intensifying drought conditions. New Braunfels Herald-Zeitung (Texas), Aug 14, 2023

Some fishing spots in Bell County have gone dry, due to drought, leaving fewer fishing opportunities. Winkler Park Campsite and Own Creek near Gatesville were dry. Lake Belton was 60% full, compared to 62% two weeks ago. The lake was at 77.7% at this time last year. KWTX TV 10 (Waco, Texas), Aug 16, 2023

5-Day Uncertainty Track last updated Thu, 17 Aug 2023 14:51:52 GMT


Wind Speed Probabilities last updated Thu, 17 Aug 2023 15:22:49 GMT

Issued at 500 AM HST Thu Aug 17 2023 190 WTPZ42 KNHC 171450 TCDEP2 Post-Tropical Cyclone Fernanda Discussion Number 20 NWS National Hurricane Center Miami FL EP072023 500 AM HST Thu Aug 17 2023 Fernanda has lacked convective activity since yesterday evening and is therefore considered a post-tropical cyclone. With no convective activity, Dvorak estimates are no longer a reliable source for intensity guidance. The initial intensity is lowered to 30 kt for this advisory largely based on the trend in geostationary satellite imagery. An occasional burst of convection is still possible given 25-26 degrees C sea surface temperatures along the forecast track of Fernanda. Model guidance indicates the cyclone will continue to weaken in an increasingly dry and stable environment for the next few days and is likely to dissipate by day 3. The remnant low is moving westward at 13 kt. This general motion is expected to continue for the next few days as the system is steered by the low-level flow around a ridge to its north. For additional information on the remnant low please see High Seas Forecasts issued by the National Weather Service. Those forecasts can be found under AWIPS header NFDHSFEPI and WMO header FZPN02 KWBC, and on the web at ocean.weather.gov/shtml/NFDHSFEPI.php. FORECAST POSITIONS AND MAX WINDS INIT 17/1500Z 16.4N 132.2W 30 KT 35 MPH...POST-TROPICAL 12H 18/0000Z 16.4N 134.1W 25 KT 30 MPH...POST-TROP/REMNT LOW 24H 18/1200Z 16.4N 136.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 36H 19/0000Z 16.4N 139.2W 25 KT 30 MPH...POST-TROP/REMNT LOW 48H 19/1200Z 16.3N 141.7W 20 KT 25 MPH...POST-TROP/REMNT LOW 60H 20/0000Z 16.4N 144.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 20/1200Z...DISSIPATED $$ Forecaster Bucci

Issued at 1500 UTC THU AUG 17 2023 000 FOPZ12 KNHC 171450 PWSEP2 POST-TROPICAL CYCLONE FERNANDA WIND SPEED PROBABILITIES NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 1500 UTC THU AUG 17 2023 AT 1500Z THE CENTER OF POST-TROPICAL CYCLONE FERNANDA WAS LOCATED NEAR LATITUDE 16.4 NORTH...LONGITUDE 132.2 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 30 KTS...35 MPH...55 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 12Z THU 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 12Z THU 00Z FRI 12Z FRI 00Z SAT 12Z SAT 12Z SUN 12Z MON PERIODS TO TO TO TO TO TO TO 00Z FRI 12Z FRI 00Z SAT 12Z SAT 12Z SUN 12Z MON 12Z TUE FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT $$ FORECASTER BUCCI

Issued at 500 AM HST Thu Aug 17 2023 000 WTPZ32 KNHC 171450 TCPEP2 BULLETIN Post-Tropical Cyclone Fernanda Advisory Number 20 NWS National Hurricane Center Miami FL EP072023 500 AM HST Thu Aug 17 2023 ...FERNANDA BECOMES A REMNANT LOW... ...THIS IS THE LAST NHC ADVISORY... SUMMARY OF 500 AM HST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...16.4N 132.2W ABOUT 1515 MI...2440 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...W OR 270 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 AM HST (1500 UTC), the center of Post-Tropical Cyclone Fernanda was located near latitude 16.4 North, longitude 132.2 West. The post-tropical cyclone is moving toward the west near 15 mph (24 km/h) and this general motion is expected to continue for the next few days. Maximum sustained winds have decreased to near 35 mph (55 km/h) with higher gusts. Continued weakening is forecast during the next couple of days, and Fernanda is likely to dissipate by the weekend. The estimated minimum central pressure is 1005 mb (29.68 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on this system. $$ Forecaster Bucci

...FERNANDA BECOMES A REMNANT LOW... ...THIS IS THE LAST NHC ADVISORY... As of 5:00 AM HST Thu Aug 17 the center of Fernanda was located near 16.4, -132.2 with movement W at 15 mph. The minimum central pressure was 1005 mb with maximum sustained winds of about 35 mph.

Issued at 1500 UTC THU AUG 17 2023 000 WTPZ22 KNHC 171449 TCMEP2 POST-TROPICAL CYCLONE FERNANDA FORECAST/ADVISORY NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 1500 UTC THU AUG 17 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). POST-TROPICAL CYCLONE CENTER LOCATED NEAR 16.4N 132.2W AT 17/1500Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 13 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT. 12 FT SEAS.. 90NE 30SE 30SW 90NW. 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 16.4N 132.2W AT 17/1500Z AT 17/1200Z CENTER WAS LOCATED NEAR 16.4N 131.5W FORECAST VALID 18/0000Z 16.4N 134.1W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 18/1200Z 16.4N 136.6W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 19/0000Z 16.4N 139.2W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 19/1200Z 16.3N 141.7W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 20/0000Z 16.4N 144.4W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 20/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.4N 132.2W THIS IS THE LAST FORECAST/ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON THIS SYSTEM. FOR ADDITIONAL INFORMATION ON THE REMNANT LOW PLEASE SEE HIGH SEAS FORECASTS ISSUED BY THE NATION WEATHER SERVICE...UNDER AWIPS HEADER NFDHSFEPI AND WMO HEADER FZPN02 KWBC. $$ FORECASTER BUCCI

The City of Lampasas entered Stage 4 Drought Response, or critical water shortage conditions, on Aug. 15, due to the low level of Stillhouse Hollow Reservoir. Lawn watering is permitted once weekly. Water may not be used to wash motor vehicles, except in the immediate interest of public health, safety and welfare. Pools may not be filled or refilled. KWTX-TV 10 News Waco (Texas), Aug 16, 2023

A Vermilion Parish rice farmer stated that he has kept the wells pumping for the past two and a half to three months since no rain has fallen. KATC (Lafayette, La.), Aug 16, 2023

Kittitas County residents were urged to conserve water amid ongoing drought. Water rights have been secured for junior groundwater uses associated with small-scale and individual well use, offering more security during droughts. KNDU-TV NBC 5 Kennewick (Wash.), Aug 16, 2023

The City of Beaumont was experiencing so many water main breaks that they were considering hiring contractors to assist with water main repairs as extreme heat and drought continued to take a toll. Water conservation was mandatory under the stage 3 restrictions. 12 News KBMT (Beaumont, Texas), Aug 16, 2023

Algae in Lake Manatee caused drinking water to taste unpleasant last month, but the peculiar taste should be gone. The algae continued to bloom amid drought conditions and was expected to persist until the drought ends. Sarasota Herald-Tribune (Fla.), Aug 16, 2023

Pasture grasses in Osceola County mostly dried up in May and June amid the hot, dry weather. Many area beef farmers had to feed hay supplies intended to be used in the winter months, meaning that more hay will have to be purchased for the winter. Some cattle may also be sold before winter. Drought hurt the hay crop. Yields from the first cutting were 20% to 40% less than normal. Drought also decreased the size of the second cutting of hay. Christmas trees were affected by the dry weather, too. Growers lost 10% to 40% of the seedlings planted this year. Christmas tree prices will not be impacted immediately, but may show up years from now if there is a shortage of trees. Cadillac News (Mich.), Aug 16, 2023