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5-Day Uncertainty Track last updated Sun, 22 Sep 2019 20:36:29 GMT


Wind Speed Probabilities last updated Sun, 22 Sep 2019 21:39:02 GMT

Issued at 1100 AM HST Sun Sep 22 2019 000 WTPZ43 KNHC 222035 TCDEP3 Tropical Storm Kiko Discussion Number 42 NWS National Hurricane Center Miami FL EP132019 1100 AM HST Sun Sep 22 2019 Not much can be added to Kiko after nearly 10 days describing the cyclone. It still consists of a tight circulation of low clouds with intermittent bursts of deep convection. Based on Dvorak estimates the initial intensity is kept at 35 kts. Kiko has the opportunity to strengthen a little bit in one of those burst, but the general trend is for Kiko to weaken and become a remnant low as it crosses the end of our domain. Kiko is moving toward the west-southwest at 6 knots steered by the subtropical ridge and its associated trades. Kiko will continue swinging south of west and north of due west as the subtropical high pulses during the next few days. FORECAST POSITIONS AND MAX WINDS INIT 22/2100Z 16.1N 133.9W 35 KT 40 MPH 12H 23/0600Z 15.7N 134.8W 35 KT 40 MPH 24H 23/1800Z 16.0N 136.2W 35 KT 40 MPH 36H 24/0600Z 17.2N 137.3W 40 KT 45 MPH 48H 24/1800Z 18.5N 138.5W 40 KT 45 MPH 72H 25/1800Z 19.0N 140.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 26/1800Z 18.5N 141.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 27/1800Z 17.5N 142.0W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Avila

Issued at 2100 UTC SUN SEP 22 2019 000 FOPZ13 KNHC 222034 PWSEP3 TROPICAL STORM KIKO WIND SPEED PROBABILITIES NUMBER 42 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132019 2100 UTC SUN SEP 22 2019 AT 2100Z THE CENTER OF TROPICAL STORM KIKO WAS LOCATED NEAR LATITUDE 16.1 NORTH...LONGITUDE 133.9 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 15N 135W 34 6 5(11) 2(13) X(13) X(13) X(13) X(13) 20N 135W 34 X 1( 1) 1( 2) 1( 3) 1( 4) X( 4) 1( 5) 15N 140W 34 X X( X) 1( 1) 1( 2) 2( 4) 1( 5) 1( 6) 20N 140W 34 X X( X) 1( 1) 6( 7) 12(19) 2(21) 1(22) 20N 140W 50 X X( X) X( X) X( X) 3( 3) X( 3) X( 3) $$ FORECASTER AVILA

Issued at 1100 AM HST Sun Sep 22 2019 000 WTPZ33 KNHC 222034 TCPEP3 BULLETIN Tropical Storm Kiko Advisory Number 42 NWS National Hurricane Center Miami FL EP132019 1100 AM HST Sun Sep 22 2019 ...KIKO REFUSES TO GO AWAY... SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION ----------------------------------------------- LOCATION...16.1N 133.9W ABOUT 1630 MI...2620 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...WSW OR 250 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...1006 MB...29.71 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 Kiko was located near latitude 16.1 North, longitude 133.9 West. Kiko is moving toward the west-southwest near 7 mph (11 km/h). A swinging motion between the west-southwest and the west-northwest is forecast to continue through the next few days. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Some small fluctuations in strength are expected during the next 2 to 3 days. Tropical-storm-force winds extend outward up to 35 miles (55 km) from the center. The estimated minimum central pressure is 1006 mb (29.71 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 500 PM HST. $$ Forecaster Avila

...KIKO REFUSES TO GO AWAY... As of 11:00 AM HST Sun Sep 22 the center of Kiko was located near 16.1, -133.9 with movement WSW at 7 mph. The minimum central pressure was 1006 mb with maximum sustained winds of about 40 mph.

Issued at 2100 UTC SUN SEP 22 2019 000 WTPZ23 KNHC 222034 TCMEP3 TROPICAL STORM KIKO FORECAST/ADVISORY NUMBER 42 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132019 2100 UTC SUN SEP 22 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 16.1N 133.9W AT 22/2100Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-SOUTHWEST OR 250 DEGREES AT 6 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1006 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 30NE 0SE 0SW 30NW. 12 FT SEAS.. 45NE 0SE 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 16.1N 133.9W AT 22/2100Z AT 22/1800Z CENTER WAS LOCATED NEAR 16.2N 133.6W FORECAST VALID 23/0600Z 15.7N 134.8W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 30NE 0SE 0SW 30NW. FORECAST VALID 23/1800Z 16.0N 136.2W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 30NE 10SE 30SW 30NW. FORECAST VALID 24/0600Z 17.2N 137.3W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 40NE 20SE 20SW 30NW. FORECAST VALID 24/1800Z 18.5N 138.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 20SE 20SW 40NW. FORECAST VALID 25/1800Z 19.0N 140.5W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 150 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 26/1800Z 18.5N 141.0W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. OUTLOOK VALID 27/1800Z 17.5N 142.0W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.1N 133.9W NEXT ADVISORY AT 23/0300Z $$ FORECASTER AVILA

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sun Sep 22 2019 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS EXTENDING FROM PARTS OF OKLAHOMA NORTHEASTWARD TO INDIANA... ...SUMMARY... Isolated damaging winds, and perhaps a tornado or two, will remain possible through this evening from parts of Oklahoma to Indiana. ...20Z Update... No changes have been made to the Marginal Risk extending from central OK northeastward to IL and far northwestern IN. A broad area of persistent rain showers across parts of MO into IL has hampered diurnal heating and the development of instability across this area. Relatively better, but still limited, severe potential may exist in a narrow corridor from parts of northern/central OK into southeastern KS and far western MO ahead of a surface cold front. MLCAPE around 500-1000 J/kg is in place across this region as some cloud breaks have allowed for modest diurnal heating. Strong shear remains over this region, which may support isolated strong/gusty downdraft winds. An isolated/marginal severe risk may also exist from the St. Louis metro area northeastward into central IL through the rest of the afternoon, as a small increase in instability in the presence of strong shear has occurred on the eastern edge of the broad precipitation shield over MO. ..Gleason.. 09/22/2019 .PREV DISCUSSION... /ISSUED 1117 AM CDT Sun Sep 22 2019/ ...OK to IL... No changes have been made to the ongoing forecast. A band of relatively fast winds aloft extends from the southern and central Plains into the mid MS valley and Great Lakes region today. A strong shortwave trough embedded in this flow over western KS/OK will track into MO/IL during this forecast period. Considerable cloud cover and areas of precipitation will continue to affect the MRGL risk corridor this afternoon. Despite the weak instability and poor lapse rates, forecast soundings show sufficient vertical shear to pose a limited risk of a storm or two becoming intense with damaging wind potential and some tornado risk. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sun Sep 22 2019 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS EXTENDING FROM PARTS OF OKLAHOMA NORTHEASTWARD TO INDIANA... ...SUMMARY... Isolated damaging winds, and perhaps a tornado or two, will remain possible through this evening from parts of Oklahoma to Indiana. ...20Z Update... No changes have been made to the Marginal Risk extending from central OK northeastward to IL and far northwestern IN. A broad area of persistent rain showers across parts of MO into IL has hampered diurnal heating and the development of instability across this area. Relatively better, but still limited, severe potential may exist in a narrow corridor from parts of northern/central OK into southeastern KS and far western MO ahead of a surface cold front. MLCAPE around 500-1000 J/kg is in place across this region as some cloud breaks have allowed for modest diurnal heating. Strong shear remains over this region, which may support isolated strong/gusty downdraft winds. An isolated/marginal severe risk may also exist from the St. Louis metro area northeastward into central IL through the rest of the afternoon, as a small increase in instability in the presence of strong shear has occurred on the eastern edge of the broad precipitation shield over MO. ..Gleason.. 09/22/2019 .PREV DISCUSSION... /ISSUED 1117 AM CDT Sun Sep 22 2019/ ...OK to IL... No changes have been made to the ongoing forecast. A band of relatively fast winds aloft extends from the southern and central Plains into the mid MS valley and Great Lakes region today. A strong shortwave trough embedded in this flow over western KS/OK will track into MO/IL during this forecast period. Considerable cloud cover and areas of precipitation will continue to affect the MRGL risk corridor this afternoon. Despite the weak instability and poor lapse rates, forecast soundings show sufficient vertical shear to pose a limited risk of a storm or two becoming intense with damaging wind potential and some tornado risk. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sun Sep 22 2019 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS EXTENDING FROM PARTS OF OKLAHOMA NORTHEASTWARD TO INDIANA... ...SUMMARY... Isolated damaging winds, and perhaps a tornado or two, will remain possible through this evening from parts of Oklahoma to Indiana. ...20Z Update... No changes have been made to the Marginal Risk extending from central OK northeastward to IL and far northwestern IN. A broad area of persistent rain showers across parts of MO into IL has hampered diurnal heating and the development of instability across this area. Relatively better, but still limited, severe potential may exist in a narrow corridor from parts of northern/central OK into southeastern KS and far western MO ahead of a surface cold front. MLCAPE around 500-1000 J/kg is in place across this region as some cloud breaks have allowed for modest diurnal heating. Strong shear remains over this region, which may support isolated strong/gusty downdraft winds. An isolated/marginal severe risk may also exist from the St. Louis metro area northeastward into central IL through the rest of the afternoon, as a small increase in instability in the presence of strong shear has occurred on the eastern edge of the broad precipitation shield over MO. ..Gleason.. 09/22/2019 .PREV DISCUSSION... /ISSUED 1117 AM CDT Sun Sep 22 2019/ ...OK to IL... No changes have been made to the ongoing forecast. A band of relatively fast winds aloft extends from the southern and central Plains into the mid MS valley and Great Lakes region today. A strong shortwave trough embedded in this flow over western KS/OK will track into MO/IL during this forecast period. Considerable cloud cover and areas of precipitation will continue to affect the MRGL risk corridor this afternoon. Despite the weak instability and poor lapse rates, forecast soundings show sufficient vertical shear to pose a limited risk of a storm or two becoming intense with damaging wind potential and some tornado risk. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Sun Sep 22 2019 Valid 231200Z - 241200Z Consensus among guidance exists that the LAX/TPH pressure gradient will increase late Monday into early Tuesday morning. Accordingly, high resolution guidance has forecast 15-25 mph winds in the higher terrain of Los Angeles/Ventura counties. There is still uncertainty with regard to how low overnight RH will drop in these areas as well as how long these conditions will occur. Nonetheless, trends in guidance suggest an increase in fire weather concerns for these areas and elevated highlights have been introduced for that reason. ..Wendt.. 09/22/2019 .PREV DISCUSSION... /ISSUED 0130 AM CDT Sun Sep 22 2019/ ...Synopsis... A strong mid/upper-level trough -- and associated area of enhanced mid-level flow -- is forecast to gradually move southeastward from the Great Basin to the Desert Southwest Day 2/Monday. ...Northern California... Elevated to locally critical fire weather conditions are expected Day 2/Monday across portions of the Sacramento Valley (especially western portions of the valley) and adjacent North Coast Ranges, as dry/gusty low-level northerly flow -- beneath the aforementioned area of enhanced mid-level flow -- overlaps near critical minimum RH values and at least marginally receptive fuels. Elevated fire weather conditions may also persist into the overnight due to poor RH recoveries and lingering gusty/breezy surface winds -- especially in terrain favored areas of the North Coast Ranges. ...Southern California... While a combination of increasing offshore surface flow and poor overnight RH recoveries may promote at least locally elevated fire weather conditions late overnight Day 2/Monday, the uncertainty regarding timing/coverage of any fire weather conditions precludes a fire weather area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Sun Sep 22 2019 Valid 231200Z - 241200Z Consensus among guidance exists that the LAX/TPH pressure gradient will increase late Monday into early Tuesday morning. Accordingly, high resolution guidance has forecast 15-25 mph winds in the higher terrain of Los Angeles/Ventura counties. There is still uncertainty with regard to how low overnight RH will drop in these areas as well as how long these conditions will occur. Nonetheless, trends in guidance suggest an increase in fire weather concerns for these areas and elevated highlights have been introduced for that reason. ..Wendt.. 09/22/2019 .PREV DISCUSSION... /ISSUED 0130 AM CDT Sun Sep 22 2019/ ...Synopsis... A strong mid/upper-level trough -- and associated area of enhanced mid-level flow -- is forecast to gradually move southeastward from the Great Basin to the Desert Southwest Day 2/Monday. ...Northern California... Elevated to locally critical fire weather conditions are expected Day 2/Monday across portions of the Sacramento Valley (especially western portions of the valley) and adjacent North Coast Ranges, as dry/gusty low-level northerly flow -- beneath the aforementioned area of enhanced mid-level flow -- overlaps near critical minimum RH values and at least marginally receptive fuels. Elevated fire weather conditions may also persist into the overnight due to poor RH recoveries and lingering gusty/breezy surface winds -- especially in terrain favored areas of the North Coast Ranges. ...Southern California... While a combination of increasing offshore surface flow and poor overnight RH recoveries may promote at least locally elevated fire weather conditions late overnight Day 2/Monday, the uncertainty regarding timing/coverage of any fire weather conditions precludes a fire weather area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Sun Sep 22 2019 Valid 231200Z - 241200Z Consensus among guidance exists that the LAX/TPH pressure gradient will increase late Monday into early Tuesday morning. Accordingly, high resolution guidance has forecast 15-25 mph winds in the higher terrain of Los Angeles/Ventura counties. There is still uncertainty with regard to how low overnight RH will drop in these areas as well as how long these conditions will occur. Nonetheless, trends in guidance suggest an increase in fire weather concerns for these areas and elevated highlights have been introduced for that reason. ..Wendt.. 09/22/2019 .PREV DISCUSSION... /ISSUED 0130 AM CDT Sun Sep 22 2019/ ...Synopsis... A strong mid/upper-level trough -- and associated area of enhanced mid-level flow -- is forecast to gradually move southeastward from the Great Basin to the Desert Southwest Day 2/Monday. ...Northern California... Elevated to locally critical fire weather conditions are expected Day 2/Monday across portions of the Sacramento Valley (especially western portions of the valley) and adjacent North Coast Ranges, as dry/gusty low-level northerly flow -- beneath the aforementioned area of enhanced mid-level flow -- overlaps near critical minimum RH values and at least marginally receptive fuels. Elevated fire weather conditions may also persist into the overnight due to poor RH recoveries and lingering gusty/breezy surface winds -- especially in terrain favored areas of the North Coast Ranges. ...Southern California... While a combination of increasing offshore surface flow and poor overnight RH recoveries may promote at least locally elevated fire weather conditions late overnight Day 2/Monday, the uncertainty regarding timing/coverage of any fire weather conditions precludes a fire weather area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Sun Sep 22 2019 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN/CENTRAL ARIZONA... ...SUMMARY... Scattered storms, some of which may be severe with damaging winds and large hail, appear possible over much of Arizona on Monday. ...Arizona into Southwestern New Mexico... Embedded within large-scale upper troughing over much of the western CONUS, an upper trough/low will develop southward across the western Great Basin into the Southwest through the period. In advance of this feature, low-level moisture is forecast to rapidly increase along the CA/AZ border eastward into southern/central AZ by early Monday morning. There are some indications that isolated showers/storms may be ongoing at the start of the period Monday morning across mainly southern AZ. The effect that this possible early convection may have on destabilization and severe storm potential later in the day remains unclear. Regardless, strengthening west-southwesterly winds at mid levels in combination with increasing instability suggest that at least isolated severe storms will be possible across much of southern/central AZ Monday afternoon and evening. MLCAPE should reach to around 1000-1500 J/kg from the Mogollon Rim southward, with locally higher values possible in far western AZ. 35-50 kt of effective bulk shear will support supercells, with initial convective development probably occurring along or just east of the CA/AZ border. Isolated large hail will be possible with these mainly discrete storms, as generally straight hodographs become elongated at mid/upper levels. As storms spread eastward through the afternoon, some clustering may occur as low-level lapse rates steepen through diurnal heating and mixing of the boundary layer. Damaging winds may become an increasing concern with eastward extent across southern/central AZ into Monday evening if this upscale growth occurs. An isolated severe threat may persist Monday night into parts of southwestern NM before instability eventually wanes. Across northern AZ, both low-level moisture and related instability are forecast to be weaker, with a more isolated/marginal hail/wind threat. ...Northeast... An upper trough/low will move quickly eastward from the Great Lakes across the Northeast, OH Valley, and Mid-Atlantic on Monday. Strong mid/upper-level winds will be present across these regions in association with the upper trough/low. At the surface, a cold front will likewise sweep eastward across these regions through the day. Mid-level lapse rates over these areas are expected to remain quite meager, and widespread cloudiness will likely be present. But, surface dewpoints generally in the low to mid 60s ahead of the front and modest diurnal heating will probably support weak instability by Monday afternoon along/ahead of the front. MLCAPE should generally remain at or below 500 J/kg. This meager instability will probably temper the overall severe threat, even though strong shear will be present owing to the strengthening wind field through mid/upper levels. While some strong/gusty downdraft winds cannot be completely ruled out with rain showers or any low-topped storms that develop, the lack of stronger forecast instability precludes introduction of 5% severe probabilities for wind at this time. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Gleason.. 09/22/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Sun Sep 22 2019 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN/CENTRAL ARIZONA... ...SUMMARY... Scattered storms, some of which may be severe with damaging winds and large hail, appear possible over much of Arizona on Monday. ...Arizona into Southwestern New Mexico... Embedded within large-scale upper troughing over much of the western CONUS, an upper trough/low will develop southward across the western Great Basin into the Southwest through the period. In advance of this feature, low-level moisture is forecast to rapidly increase along the CA/AZ border eastward into southern/central AZ by early Monday morning. There are some indications that isolated showers/storms may be ongoing at the start of the period Monday morning across mainly southern AZ. The effect that this possible early convection may have on destabilization and severe storm potential later in the day remains unclear. Regardless, strengthening west-southwesterly winds at mid levels in combination with increasing instability suggest that at least isolated severe storms will be possible across much of southern/central AZ Monday afternoon and evening. MLCAPE should reach to around 1000-1500 J/kg from the Mogollon Rim southward, with locally higher values possible in far western AZ. 35-50 kt of effective bulk shear will support supercells, with initial convective development probably occurring along or just east of the CA/AZ border. Isolated large hail will be possible with these mainly discrete storms, as generally straight hodographs become elongated at mid/upper levels. As storms spread eastward through the afternoon, some clustering may occur as low-level lapse rates steepen through diurnal heating and mixing of the boundary layer. Damaging winds may become an increasing concern with eastward extent across southern/central AZ into Monday evening if this upscale growth occurs. An isolated severe threat may persist Monday night into parts of southwestern NM before instability eventually wanes. Across northern AZ, both low-level moisture and related instability are forecast to be weaker, with a more isolated/marginal hail/wind threat. ...Northeast... An upper trough/low will move quickly eastward from the Great Lakes across the Northeast, OH Valley, and Mid-Atlantic on Monday. Strong mid/upper-level winds will be present across these regions in association with the upper trough/low. At the surface, a cold front will likewise sweep eastward across these regions through the day. Mid-level lapse rates over these areas are expected to remain quite meager, and widespread cloudiness will likely be present. But, surface dewpoints generally in the low to mid 60s ahead of the front and modest diurnal heating will probably support weak instability by Monday afternoon along/ahead of the front. MLCAPE should generally remain at or below 500 J/kg. This meager instability will probably temper the overall severe threat, even though strong shear will be present owing to the strengthening wind field through mid/upper levels. While some strong/gusty downdraft winds cannot be completely ruled out with rain showers or any low-topped storms that develop, the lack of stronger forecast instability precludes introduction of 5% severe probabilities for wind at this time. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Gleason.. 09/22/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Sun Sep 22 2019 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN/CENTRAL ARIZONA... ...SUMMARY... Scattered storms, some of which may be severe with damaging winds and large hail, appear possible over much of Arizona on Monday. ...Arizona into Southwestern New Mexico... Embedded within large-scale upper troughing over much of the western CONUS, an upper trough/low will develop southward across the western Great Basin into the Southwest through the period. In advance of this feature, low-level moisture is forecast to rapidly increase along the CA/AZ border eastward into southern/central AZ by early Monday morning. There are some indications that isolated showers/storms may be ongoing at the start of the period Monday morning across mainly southern AZ. The effect that this possible early convection may have on destabilization and severe storm potential later in the day remains unclear. Regardless, strengthening west-southwesterly winds at mid levels in combination with increasing instability suggest that at least isolated severe storms will be possible across much of southern/central AZ Monday afternoon and evening. MLCAPE should reach to around 1000-1500 J/kg from the Mogollon Rim southward, with locally higher values possible in far western AZ. 35-50 kt of effective bulk shear will support supercells, with initial convective development probably occurring along or just east of the CA/AZ border. Isolated large hail will be possible with these mainly discrete storms, as generally straight hodographs become elongated at mid/upper levels. As storms spread eastward through the afternoon, some clustering may occur as low-level lapse rates steepen through diurnal heating and mixing of the boundary layer. Damaging winds may become an increasing concern with eastward extent across southern/central AZ into Monday evening if this upscale growth occurs. An isolated severe threat may persist Monday night into parts of southwestern NM before instability eventually wanes. Across northern AZ, both low-level moisture and related instability are forecast to be weaker, with a more isolated/marginal hail/wind threat. ...Northeast... An upper trough/low will move quickly eastward from the Great Lakes across the Northeast, OH Valley, and Mid-Atlantic on Monday. Strong mid/upper-level winds will be present across these regions in association with the upper trough/low. At the surface, a cold front will likewise sweep eastward across these regions through the day. Mid-level lapse rates over these areas are expected to remain quite meager, and widespread cloudiness will likely be present. But, surface dewpoints generally in the low to mid 60s ahead of the front and modest diurnal heating will probably support weak instability by Monday afternoon along/ahead of the front. MLCAPE should generally remain at or below 500 J/kg. This meager instability will probably temper the overall severe threat, even though strong shear will be present owing to the strengthening wind field through mid/upper levels. While some strong/gusty downdraft winds cannot be completely ruled out with rain showers or any low-topped storms that develop, the lack of stronger forecast instability precludes introduction of 5% severe probabilities for wind at this time. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Gleason.. 09/22/2019 Read more

000
ABPZ20 KNHC 221713
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun Sep 22 2019

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

The National Hurricane Center is issuing advisories on Tropical
Depression Mario, located a few hundred miles south of the southern
tip of the Baja California peninsula, and on Tropical Storm Kiko,
located over the far southwestern part of the basin. The National
Hurricane Center has issued the last advisory on Tropical Depression
Lorena which degenerated into a broad area of low pressure over
northwestern Mexico.

Tropical cyclone formation is not expected for the next 5 days.

$$
Forecaster Avila

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1200 PM CDT Sun Sep 22 2019 Valid 221700Z - 231200Z ...NO CRITICAL AREAS... Current water vapor satellite imagery shows a potent mid-level trough beginning to dig into northern California. Dry air aloft is quite evident with this feature and is forecast to impact portions of the Northern Coastal Ranges during the overnight. Forecast soundings capture this dry air aloft well, though relatively efficient boundary-layer cooling in these soundings keeps this air from mixing to the surface. However, some concern exists that strong surface flow in localized areas will promote greater overnight mixing than models suggest. High-resolution guidance continues to the suggest that this will only occur on a spatially-limited basis so no highlights will be introduced. ..Wendt.. 09/22/2019 .PREV DISCUSSION... /ISSUED 0126 AM CDT Sun Sep 22 2019/ ...Synopsis... An area of mid-level ridging is forecast to move from portions of the Great Basin toward the central/northern Plains through tonight. Meanwhile, a large upstream mid/upper-level trough -- and associated area of enhanced mid-level flow -- is forecast to come onshore across portions of northern California, Oregon, and Washington late this afternoon and into the overnight. ...Nevada... A few hours of locally elevated fire weather conditions are possible this afternoon across portions of central/southwest Nevada, where sustained surface winds of 10-15 mph occur in conjunction with surface RH values near 15% and receptive fuels. However, the brief/spotty nature of these conditions precludes the introduction of a fire weather area. ...Northern California... Locally elevated fire weather conditions are possible late this evening and into tonight across eastern portions of the Northern Coast Ranges, as a tightening surface pressure gradient coupled with overlapping enhanced mid-level flow promotes increasingly gusty surface winds amidst pockets of poor overnight RH recoveries. A fire area may be needed in a future update if trends in guidance suggest greater coverage of elevated fire weather conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1200 PM CDT Sun Sep 22 2019 Valid 221700Z - 231200Z ...NO CRITICAL AREAS... Current water vapor satellite imagery shows a potent mid-level trough beginning to dig into northern California. Dry air aloft is quite evident with this feature and is forecast to impact portions of the Northern Coastal Ranges during the overnight. Forecast soundings capture this dry air aloft well, though relatively efficient boundary-layer cooling in these soundings keeps this air from mixing to the surface. However, some concern exists that strong surface flow in localized areas will promote greater overnight mixing than models suggest. High-resolution guidance continues to the suggest that this will only occur on a spatially-limited basis so no highlights will be introduced. ..Wendt.. 09/22/2019 .PREV DISCUSSION... /ISSUED 0126 AM CDT Sun Sep 22 2019/ ...Synopsis... An area of mid-level ridging is forecast to move from portions of the Great Basin toward the central/northern Plains through tonight. Meanwhile, a large upstream mid/upper-level trough -- and associated area of enhanced mid-level flow -- is forecast to come onshore across portions of northern California, Oregon, and Washington late this afternoon and into the overnight. ...Nevada... A few hours of locally elevated fire weather conditions are possible this afternoon across portions of central/southwest Nevada, where sustained surface winds of 10-15 mph occur in conjunction with surface RH values near 15% and receptive fuels. However, the brief/spotty nature of these conditions precludes the introduction of a fire weather area. ...Northern California... Locally elevated fire weather conditions are possible late this evening and into tonight across eastern portions of the Northern Coast Ranges, as a tightening surface pressure gradient coupled with overlapping enhanced mid-level flow promotes increasingly gusty surface winds amidst pockets of poor overnight RH recoveries. A fire area may be needed in a future update if trends in guidance suggest greater coverage of elevated fire weather conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1200 PM CDT Sun Sep 22 2019 Valid 221700Z - 231200Z ...NO CRITICAL AREAS... Current water vapor satellite imagery shows a potent mid-level trough beginning to dig into northern California. Dry air aloft is quite evident with this feature and is forecast to impact portions of the Northern Coastal Ranges during the overnight. Forecast soundings capture this dry air aloft well, though relatively efficient boundary-layer cooling in these soundings keeps this air from mixing to the surface. However, some concern exists that strong surface flow in localized areas will promote greater overnight mixing than models suggest. High-resolution guidance continues to the suggest that this will only occur on a spatially-limited basis so no highlights will be introduced. ..Wendt.. 09/22/2019 .PREV DISCUSSION... /ISSUED 0126 AM CDT Sun Sep 22 2019/ ...Synopsis... An area of mid-level ridging is forecast to move from portions of the Great Basin toward the central/northern Plains through tonight. Meanwhile, a large upstream mid/upper-level trough -- and associated area of enhanced mid-level flow -- is forecast to come onshore across portions of northern California, Oregon, and Washington late this afternoon and into the overnight. ...Nevada... A few hours of locally elevated fire weather conditions are possible this afternoon across portions of central/southwest Nevada, where sustained surface winds of 10-15 mph occur in conjunction with surface RH values near 15% and receptive fuels. However, the brief/spotty nature of these conditions precludes the introduction of a fire weather area. ...Northern California... Locally elevated fire weather conditions are possible late this evening and into tonight across eastern portions of the Northern Coast Ranges, as a tightening surface pressure gradient coupled with overlapping enhanced mid-level flow promotes increasingly gusty surface winds amidst pockets of poor overnight RH recoveries. A fire area may be needed in a future update if trends in guidance suggest greater coverage of elevated fire weather conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Sun Sep 22 2019 Valid 221630Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS EXTENDING IN A CORRIDOR FROM OKLAHOMA NORTHEASTWARD INTO ILLINOIS... ...SUMMARY... Isolated damaging winds, and perhaps a tornado or two, will be possible through this evening from parts of Oklahoma to Illinois. ...OK to IL... No changes have been made to the ongoing forecast. A band of relatively fast winds aloft extends from the southern and central Plains into the mid MS valley and Great Lakes region today. A strong shortwave trough embedded in this flow over western KS/OK will track into MO/IL during this forecast period. Considerable cloud cover and areas of precipitation will continue to affect the MRGL risk corridor this afternoon. Despite the weak instability and poor lapse rates, forecast soundings show sufficient vertical shear to pose a limited risk of a storm or two becoming intense with damaging wind potential and some tornado risk. ..Hart/Bentley.. 09/22/2019 Read more