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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Fri Sep 13 2019 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST LOWER MI INTO NORTHERN OH... ...SUMMARY... A few severe thunderstorms with damaging winds are expected from southeast Lower Michigan into northern Ohio this afternoon. ...Southeast Lower MI into IN/OH this afternoon/evening... A midlevel low over northern MN is evolving into an open wave while moving northeastward towards James Bay, as embedded speed maxima rotate around the southeastern periphery of the low. At the surface, a cold front will progress eastward across IN/Lower MI during the day, and the warm sector will spread northeastward into southeast Lower MI ahead of the front. A corridor of surface heating is expected from IN/OH into southeast Lower MI, to the southeast of the thicker clouds associated with ongoing (pre-frontal) convection from northeast IL to central Lower MI. Midlevel lapse rates will remain rather modest (less than 7 C/km) within the warm sector today. Still, surface temperatures warming to near 80 F in southeast Lower MI and well into the 80s across IN/OH, in combination with 68-70 F boundary-layer dewpoints, will result in MLCAPE of 1000-1500 J/kg. Storms are expected to form by early afternoon from northeast IN into southeast Lower MI, and then continue eastward across northern OH into this evening. Diurnal destabilization will coincide with an increase in midlevel flow/vertical shear, which will support both organized storm clusters/supercells along the cold front with a primary threat for damaging winds. A low-end tornado threat is expected from southeast Lower MI into northern OH where low-level shear/hodograph curvature will be greater near the surface warm front this afternoon/evening. The severe threat will diminish to the south in conjunction with weakening vertical shear. ...Western NC into SC this afternoon... Strong surface heating and lingering low-level moisture along and southwest of a reinforcing frontal surge could provide some focus for thunderstorm development this afternoon. Thermodynamic profiles will favor some potential for isolated damaging downbursts given DCAPE values near 1000 J/kg. ...Southeast FL coast today... Convection with gusty winds will be possible along the southeast FL coast, where northeasterly low-level winds will increase to about 30 kt around the northwest periphery of a tropical disturbance near the southeast Bahamas. Moist profiles, however, should limit the potential stronger/damaging outflow winds. ..Thompson/Gleason.. 09/13/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Fri Sep 13 2019 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST LOWER MI INTO NORTHERN OH... ...SUMMARY... A few severe thunderstorms with damaging winds are expected from southeast Lower Michigan into northern Ohio this afternoon. ...Southeast Lower MI into IN/OH this afternoon/evening... A midlevel low over northern MN is evolving into an open wave while moving northeastward towards James Bay, as embedded speed maxima rotate around the southeastern periphery of the low. At the surface, a cold front will progress eastward across IN/Lower MI during the day, and the warm sector will spread northeastward into southeast Lower MI ahead of the front. A corridor of surface heating is expected from IN/OH into southeast Lower MI, to the southeast of the thicker clouds associated with ongoing (pre-frontal) convection from northeast IL to central Lower MI. Midlevel lapse rates will remain rather modest (less than 7 C/km) within the warm sector today. Still, surface temperatures warming to near 80 F in southeast Lower MI and well into the 80s across IN/OH, in combination with 68-70 F boundary-layer dewpoints, will result in MLCAPE of 1000-1500 J/kg. Storms are expected to form by early afternoon from northeast IN into southeast Lower MI, and then continue eastward across northern OH into this evening. Diurnal destabilization will coincide with an increase in midlevel flow/vertical shear, which will support both organized storm clusters/supercells along the cold front with a primary threat for damaging winds. A low-end tornado threat is expected from southeast Lower MI into northern OH where low-level shear/hodograph curvature will be greater near the surface warm front this afternoon/evening. The severe threat will diminish to the south in conjunction with weakening vertical shear. ...Western NC into SC this afternoon... Strong surface heating and lingering low-level moisture along and southwest of a reinforcing frontal surge could provide some focus for thunderstorm development this afternoon. Thermodynamic profiles will favor some potential for isolated damaging downbursts given DCAPE values near 1000 J/kg. ...Southeast FL coast today... Convection with gusty winds will be possible along the southeast FL coast, where northeasterly low-level winds will increase to about 30 kt around the northwest periphery of a tropical disturbance near the southeast Bahamas. Moist profiles, however, should limit the potential stronger/damaging outflow winds. ..Thompson/Gleason.. 09/13/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Fri Sep 13 2019 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST LOWER MI INTO NORTHERN OH... ...SUMMARY... A few severe thunderstorms with damaging winds are expected from southeast Lower Michigan into northern Ohio this afternoon. ...Southeast Lower MI into IN/OH this afternoon/evening... A midlevel low over northern MN is evolving into an open wave while moving northeastward towards James Bay, as embedded speed maxima rotate around the southeastern periphery of the low. At the surface, a cold front will progress eastward across IN/Lower MI during the day, and the warm sector will spread northeastward into southeast Lower MI ahead of the front. A corridor of surface heating is expected from IN/OH into southeast Lower MI, to the southeast of the thicker clouds associated with ongoing (pre-frontal) convection from northeast IL to central Lower MI. Midlevel lapse rates will remain rather modest (less than 7 C/km) within the warm sector today. Still, surface temperatures warming to near 80 F in southeast Lower MI and well into the 80s across IN/OH, in combination with 68-70 F boundary-layer dewpoints, will result in MLCAPE of 1000-1500 J/kg. Storms are expected to form by early afternoon from northeast IN into southeast Lower MI, and then continue eastward across northern OH into this evening. Diurnal destabilization will coincide with an increase in midlevel flow/vertical shear, which will support both organized storm clusters/supercells along the cold front with a primary threat for damaging winds. A low-end tornado threat is expected from southeast Lower MI into northern OH where low-level shear/hodograph curvature will be greater near the surface warm front this afternoon/evening. The severe threat will diminish to the south in conjunction with weakening vertical shear. ...Western NC into SC this afternoon... Strong surface heating and lingering low-level moisture along and southwest of a reinforcing frontal surge could provide some focus for thunderstorm development this afternoon. Thermodynamic profiles will favor some potential for isolated damaging downbursts given DCAPE values near 1000 J/kg. ...Southeast FL coast today... Convection with gusty winds will be possible along the southeast FL coast, where northeasterly low-level winds will increase to about 30 kt around the northwest periphery of a tropical disturbance near the southeast Bahamas. Moist profiles, however, should limit the potential stronger/damaging outflow winds. ..Thompson/Gleason.. 09/13/2019 Read more

000
ABPZ20 KNHC 131149
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Fri Sep 13 2019

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

The National Hurricane Center is issuing advisories on Tropical
Storm Kiko, located several hundred miles south-southwest of the
southern tip of the Baja California peninsula.

Disorganized showers and thunderstorms located about 1600 miles
west-southwest of the southern tip of the Baja California peninsula
are associated with a tropical wave. Only some slight development is
expected over the next couple of days before environmental
conditions become unfavorable for development.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

Another tropical wave located several hundred miles south-southwest
of Acapulco, Mexico, is also producing disorganized showers and
thunderstorms, mainly to the west of the wave axis. Some slow
development is possible into next week while the system moves
generally westward at 5 to 10 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...30 percent.

An area of low pressure is expected to form west of the coast of
Central America over the weekend. Environmental conditions are
forecast to be conducive for development, and a tropical
depression will likely form by the middle of next week while the
system moves west-northwestward parallel to the coast of Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...high...70 percent.

&&
Public Advisories on Kiko are issued under WMO header WTPZ33 KNHC
and under AWIPS header MIATCPEP3. Forecast/Advisories on Kiko are
issued under WMO header WTPZ23 KNHC and under AWIPS header
MIATCMEP3.

$$
Forecaster Latto

5-Day Uncertainty Track last updated Fri, 13 Sep 2019 09:00:02 GMT


Wind Speed Probabilities last updated Fri, 13 Sep 2019 09:31:23 GMT

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CDT Fri Sep 13 2019 Valid 161200Z - 211200Z ...DISCUSSION... The medium-range models generally indicate that a significant short wave impulse will emerge from the base of initially amplified large-scale mid-level troughing, near the Pacific coast at the start of the period. It appears probable that this perturbation will accelerate northeastward across the northern Rockies and Plains, and north of the international border by Wednesday night, accompanied by modest surface cyclogenesis from eastern Montana through the Hudson Bay vicinity. This seems to provide the primary focus for any appreciable severe thunderstorm potential across the U.S. during this period, which could impact areas from the immediate lee of the northern Rockies into the northern Plains Tuesday through Tuesday night, and portions of the Upper Midwest on Wednesday. However, the extent of this potential remains unclear at this time, and may considerably hinge on sub-synoptic developments with low predictability in this extended forecast time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CDT Fri Sep 13 2019 Valid 161200Z - 211200Z ...DISCUSSION... The medium-range models generally indicate that a significant short wave impulse will emerge from the base of initially amplified large-scale mid-level troughing, near the Pacific coast at the start of the period. It appears probable that this perturbation will accelerate northeastward across the northern Rockies and Plains, and north of the international border by Wednesday night, accompanied by modest surface cyclogenesis from eastern Montana through the Hudson Bay vicinity. This seems to provide the primary focus for any appreciable severe thunderstorm potential across the U.S. during this period, which could impact areas from the immediate lee of the northern Rockies into the northern Plains Tuesday through Tuesday night, and portions of the Upper Midwest on Wednesday. However, the extent of this potential remains unclear at this time, and may considerably hinge on sub-synoptic developments with low predictability in this extended forecast time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CDT Fri Sep 13 2019 Valid 161200Z - 211200Z ...DISCUSSION... The medium-range models generally indicate that a significant short wave impulse will emerge from the base of initially amplified large-scale mid-level troughing, near the Pacific coast at the start of the period. It appears probable that this perturbation will accelerate northeastward across the northern Rockies and Plains, and north of the international border by Wednesday night, accompanied by modest surface cyclogenesis from eastern Montana through the Hudson Bay vicinity. This seems to provide the primary focus for any appreciable severe thunderstorm potential across the U.S. during this period, which could impact areas from the immediate lee of the northern Rockies into the northern Plains Tuesday through Tuesday night, and portions of the Upper Midwest on Wednesday. However, the extent of this potential remains unclear at this time, and may considerably hinge on sub-synoptic developments with low predictability in this extended forecast time frame. Read more

Issued at 300 AM MDT Fri Sep 13 2019 000 WTPZ43 KNHC 130852 TCDEP3 Tropical Storm Kiko Discussion Number 4 NWS National Hurricane Center Miami FL EP132019 300 AM MDT Fri Sep 13 2019 Kiko's convective pattern has still not gotten any better organized. There's a small patch of convection near the estimated center, with another larger cluster much farther south. For the most part, however, the circulation consists of a broken low- and mid-level cloud deck with a few embedded showers. Subjective Dvorak estimates from TAFB and SAB are T2.0/30 kt, while objective numbers are only slightly higher. The initial intensity is being held at 35 kt, but it's entirely possible that Kiko may not be producing tropical-storm-force winds at this time. The GOES-17 air mass product shows that Kiko is surrounded by some of the driest air over the entire tropical eastern Pacific, which could be contributing to the system's convective struggles. And going forward, it appears that the thermodynamic environment could be less than ideal for significant strengthening, with SHIPS model diagnostics showing environmental stability to be the biggest negative factor. That being said, vertical shear is expected to be less than 10 kt for at least the next 3 days, so strengthening is likely if the dry air can be mixed out of the circulation. The new NHC forecast continues to show Kiko reaching hurricane strength in about 48 hours, although the peak intensity has been tempered a bit based on the latest guidance. The official forecast is close to a blend of the Florida State Superensemble and the HFIP Corrected Consensus aids. Kiko is moving west-northwestward, or 295/9 kt, to the south of a mid-level ridge which extends along the U.S./Mexico border. This motion should continue for the next 3 days, and the track models are in good agreement on this solution. After day 3, there is a bifurcation of the models, with the GFS, HMON, COAMPS-TC, and Canadian turning Kiko northwestward or northward into a break in the ridge, and the ECMWF, UKMET, HWRF, and the consensus aids maintaining a west-northwestward or even westward heading on days 4 and 5. Due to this divergence, the updated forecast shows a slightly slower motion toward the end of the forecast period, but the track itself is very similar to the previous forecast, lying near the northern boundary of the southern camp of models. FORECAST POSITIONS AND MAX WINDS INIT 13/0900Z 16.8N 113.5W 35 KT 40 MPH 12H 13/1800Z 17.1N 114.9W 40 KT 45 MPH 24H 14/0600Z 17.5N 116.6W 50 KT 60 MPH 36H 14/1800Z 17.9N 118.3W 60 KT 70 MPH 48H 15/0600Z 18.4N 120.0W 65 KT 75 MPH 72H 16/0600Z 19.4N 123.1W 65 KT 75 MPH 96H 17/0600Z 20.5N 125.5W 45 KT 50 MPH 120H 18/0600Z 21.0N 127.5W 35 KT 40 MPH $$ Forecaster Berg

Issued at 0900 UTC FRI SEP 13 2019 000 FOPZ13 KNHC 130851 PWSEP3 TROPICAL STORM KIKO WIND SPEED PROBABILITIES NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132019 0900 UTC FRI SEP 13 2019 AT 0900Z THE CENTER OF TROPICAL STORM KIKO WAS LOCATED NEAR LATITUDE 16.8 NORTH...LONGITUDE 113.5 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 06Z FRI 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 06Z FRI 18Z FRI 06Z SAT 18Z SAT 06Z SUN 06Z MON 06Z TUE PERIODS TO TO TO TO TO TO TO 18Z FRI 06Z SAT 18Z SAT 06Z SUN 06Z MON 06Z TUE 06Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ISLA CLARION 34 20 9(29) 3(32) 1(33) X(33) X(33) X(33) 15N 115W 34 1 3( 4) 3( 7) X( 7) X( 7) X( 7) X( 7) 20N 115W 34 1 4( 5) 4( 9) 2(11) X(11) X(11) X(11) 15N 120W 34 X 2( 2) 4( 6) 4(10) 4(14) X(14) X(14) 20N 120W 34 X 2( 2) 12(14) 32(46) 11(57) 1(58) X(58) 20N 120W 50 X X( X) X( X) 8( 8) 8(16) X(16) X(16) 20N 120W 64 X X( X) X( X) 2( 2) 3( 5) X( 5) X( 5) 15N 125W 34 X X( X) X( X) X( X) 3( 3) 2( 5) X( 5) 20N 125W 34 X X( X) X( X) 1( 1) 25(26) 22(48) 3(51) 20N 125W 50 X X( X) X( X) X( X) 4( 4) 11(15) 2(17) 20N 125W 64 X X( X) X( X) X( X) 1( 1) 4( 5) 1( 6) 25N 125W 34 X X( X) X( X) X( X) 1( 1) 2( 3) 1( 4) 20N 130W 34 X X( X) X( X) X( X) X( X) 2( 2) 3( 5) $$ FORECASTER BERG

Issued at 0900 UTC FRI SEP 13 2019 000 WTPZ23 KNHC 130851 TCMEP3 TROPICAL STORM KIKO FORECAST/ADVISORY NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132019 0900 UTC FRI SEP 13 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 16.8N 113.5W AT 13/0900Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 295 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 40NE 0SE 0SW 60NW. 12 FT SEAS.. 0NE 0SE 0SW 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 16.8N 113.5W AT 13/0900Z AT 13/0600Z CENTER WAS LOCATED NEAR 16.7N 113.1W FORECAST VALID 13/1800Z 17.1N 114.9W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 40NE 0SE 0SW 60NW. FORECAST VALID 14/0600Z 17.5N 116.6W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 20NE 0SE 0SW 20NW. 34 KT... 50NE 40SE 30SW 50NW. FORECAST VALID 14/1800Z 17.9N 118.3W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 50NW. FORECAST VALID 15/0600Z 18.4N 120.0W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 15NE 0SE 0SW 15NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 50NW. FORECAST VALID 16/0600Z 19.4N 123.1W MAX WIND 65 KT...GUSTS 80 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 50NW. 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 17/0600Z 20.5N 125.5W MAX WIND 45 KT...GUSTS 55 KT. OUTLOOK VALID 18/0600Z 21.0N 127.5W MAX WIND 35 KT...GUSTS 45 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.8N 113.5W NEXT ADVISORY AT 13/1500Z $$ FORECASTER BERG

Issued at 300 AM MDT Fri Sep 13 2019 000 WTPZ33 KNHC 130851 TCPEP3 BULLETIN Tropical Storm Kiko Advisory Number 4 NWS National Hurricane Center Miami FL EP132019 300 AM MDT Fri Sep 13 2019 ...KIKO MOVING THROUGH A DRY ENVIRONMENT AND NOT STRENGTHENING... SUMMARY OF 300 AM MDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...16.8N 113.5W ABOUT 480 MI...775 KM SSW 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...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 300 AM MDT (0900 UTC), the center of Tropical Storm Kiko was located near latitude 16.8 North, longitude 113.5 West. Kiko is moving toward the west-northwest near 10 mph (17 km/h), and this general motion is expected to continue through Monday. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Some strengthening is forecast during the next couple of days, and Kiko is expected to become a hurricane over the weekend. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center. The estimated minimum central pressure is 1004 mb (29.65 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 900 AM MDT. $$ Forecaster Berg

...KIKO MOVING THROUGH A DRY ENVIRONMENT AND NOT STRENGTHENING... As of 3:00 AM MDT Fri Sep 13 the center of Kiko was located near 16.8, -113.5 with movement WNW at 10 mph. The minimum central pressure was 1004 mb with maximum sustained winds of about 40 mph.

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 AM CDT Fri Sep 13 2019 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NEAR NORTHEAST FLORIDA AND GEORGIA ATLANTIC COASTAL AREAS... ...SUMMARY... Shower and thunderstorm activity associated with a tropical system may pose at least some risk for isolated tornadoes and potentially damaging wind gusts near northeast Florida and Georgia coastal areas Sunday. ...Discussion... Models indicate substantial further amplification within the westerlies during this period, including digging upper troughing near the Pacific coast, and building of much broader downstream ridging across and north of the central Canadian/U.S. border area. Remnant mid-level troughing over eastern Canada is forecast to dig southeastward across the Canadian Maritimes and northern U.S. Atlantic coast. In lower latitudes, a tropical storm may track inland of east central Florida coastal areas through northeastern Florida Sunday through Sunday night, while another perturbation continues to slowly progress through easterly flow across the western Gulf of Mexico into Texas coastal plain. One or two additional perturbations may develop northward around the western periphery of subtropical ridging, to the east of the Pacific coast troughing, across the southern Rockies into the northern Plains. Each of these features may provide support for areas of scattered thunderstorm activity Sunday and Sunday night. However, it seems probable that any appreciable severe weather potential will be limited to convective development associated with the possible tropical storm. This will considerably hinge on the track of the storm, but could include a risk for isolated tornadoes, in addition to potentially damaging wind gusts. Across the Upper Midwest and Great Lakes region, thunderstorm probabilities appear generally low and mostly in association with remnant convection from Saturday night, driven largely by warm advection. This may continue into early Sunday, before thunderstorm potential becomes more unclear as mid-level ridging builds into the region. ..Kerr.. 09/13/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 AM CDT Fri Sep 13 2019 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NEAR NORTHEAST FLORIDA AND GEORGIA ATLANTIC COASTAL AREAS... ...SUMMARY... Shower and thunderstorm activity associated with a tropical system may pose at least some risk for isolated tornadoes and potentially damaging wind gusts near northeast Florida and Georgia coastal areas Sunday. ...Discussion... Models indicate substantial further amplification within the westerlies during this period, including digging upper troughing near the Pacific coast, and building of much broader downstream ridging across and north of the central Canadian/U.S. border area. Remnant mid-level troughing over eastern Canada is forecast to dig southeastward across the Canadian Maritimes and northern U.S. Atlantic coast. In lower latitudes, a tropical storm may track inland of east central Florida coastal areas through northeastern Florida Sunday through Sunday night, while another perturbation continues to slowly progress through easterly flow across the western Gulf of Mexico into Texas coastal plain. One or two additional perturbations may develop northward around the western periphery of subtropical ridging, to the east of the Pacific coast troughing, across the southern Rockies into the northern Plains. Each of these features may provide support for areas of scattered thunderstorm activity Sunday and Sunday night. However, it seems probable that any appreciable severe weather potential will be limited to convective development associated with the possible tropical storm. This will considerably hinge on the track of the storm, but could include a risk for isolated tornadoes, in addition to potentially damaging wind gusts. Across the Upper Midwest and Great Lakes region, thunderstorm probabilities appear generally low and mostly in association with remnant convection from Saturday night, driven largely by warm advection. This may continue into early Sunday, before thunderstorm potential becomes more unclear as mid-level ridging builds into the region. ..Kerr.. 09/13/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 AM CDT Fri Sep 13 2019 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NEAR NORTHEAST FLORIDA AND GEORGIA ATLANTIC COASTAL AREAS... ...SUMMARY... Shower and thunderstorm activity associated with a tropical system may pose at least some risk for isolated tornadoes and potentially damaging wind gusts near northeast Florida and Georgia coastal areas Sunday. ...Discussion... Models indicate substantial further amplification within the westerlies during this period, including digging upper troughing near the Pacific coast, and building of much broader downstream ridging across and north of the central Canadian/U.S. border area. Remnant mid-level troughing over eastern Canada is forecast to dig southeastward across the Canadian Maritimes and northern U.S. Atlantic coast. In lower latitudes, a tropical storm may track inland of east central Florida coastal areas through northeastern Florida Sunday through Sunday night, while another perturbation continues to slowly progress through easterly flow across the western Gulf of Mexico into Texas coastal plain. One or two additional perturbations may develop northward around the western periphery of subtropical ridging, to the east of the Pacific coast troughing, across the southern Rockies into the northern Plains. Each of these features may provide support for areas of scattered thunderstorm activity Sunday and Sunday night. However, it seems probable that any appreciable severe weather potential will be limited to convective development associated with the possible tropical storm. This will considerably hinge on the track of the storm, but could include a risk for isolated tornadoes, in addition to potentially damaging wind gusts. Across the Upper Midwest and Great Lakes region, thunderstorm probabilities appear generally low and mostly in association with remnant convection from Saturday night, driven largely by warm advection. This may continue into early Sunday, before thunderstorm potential becomes more unclear as mid-level ridging builds into the region. ..Kerr.. 09/13/2019 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Fri Sep 13 2019 Valid 141200Z - 151200Z ...Synopsis... An upper trough is forecast to approach the Pacific Northwest by Saturday evening, with largely zonal flow expected further east across the interior Northwest into the northern Plains. At the surface, broad low pressure will remain in place across south-central Canada, with a surface trough extending into portions of the northern Plains. ...Southeast WY... Low-level westerly flow will become established across southern WY by Saturday afternoon, to the west of the surface trough over the northern Plains. While there remains some variability among model guidance regarding the strength of low-level flow, sustained surface winds of 15-25 mph (with higher gusts) combined with minimum RH values of 10-20% will likely result in elevated to locally critical conditions across portions of southeast WY. ..Dean.. 09/13/2019 ...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 0200 AM CDT Fri Sep 13 2019 Valid 141200Z - 151200Z ...Synopsis... An upper trough is forecast to approach the Pacific Northwest by Saturday evening, with largely zonal flow expected further east across the interior Northwest into the northern Plains. At the surface, broad low pressure will remain in place across south-central Canada, with a surface trough extending into portions of the northern Plains. ...Southeast WY... Low-level westerly flow will become established across southern WY by Saturday afternoon, to the west of the surface trough over the northern Plains. While there remains some variability among model guidance regarding the strength of low-level flow, sustained surface winds of 15-25 mph (with higher gusts) combined with minimum RH values of 10-20% will likely result in elevated to locally critical conditions across portions of southeast WY. ..Dean.. 09/13/2019 ...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 0200 AM CDT Fri Sep 13 2019 Valid 141200Z - 151200Z ...Synopsis... An upper trough is forecast to approach the Pacific Northwest by Saturday evening, with largely zonal flow expected further east across the interior Northwest into the northern Plains. At the surface, broad low pressure will remain in place across south-central Canada, with a surface trough extending into portions of the northern Plains. ...Southeast WY... Low-level westerly flow will become established across southern WY by Saturday afternoon, to the west of the surface trough over the northern Plains. While there remains some variability among model guidance regarding the strength of low-level flow, sustained surface winds of 15-25 mph (with higher gusts) combined with minimum RH values of 10-20% will likely result in elevated to locally critical conditions across portions of southeast WY. ..Dean.. 09/13/2019 ...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 0200 AM CDT Fri Sep 13 2019 Valid 131200Z - 141200Z ...Synopsis... A seasonably strong upper trough over the upper Midwest will progress eastward through the period, while a lower-amplitude trough will move quickly eastward from the northern Rockies into the northern Plains by Saturday morning. At the surface, high pressure centered over the central Rockies is expected to gradually weaken, while a weak surface low moves eastward across the southern Canadian Prairies. ...Southern California... Elevated fire weather conditions may be ongoing at the start of the period across portions of southern CA, within a weak offshore flow regime. Some weakening of the offshore gradient is expected later today, resulting in a general decrease in wind speeds, though very warm and dry conditions will persist, with poor overnight RH recovery into Saturday morning. ..Dean.. 09/13/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more