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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0255 PM CDT Wed Sep 25 2024 Valid 252000Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE GULF COAST INTO THE SOUTHERN/CENTRAL APPALACHIANS AND FLORIDA PENINSULA... ...SUMMARY... Isolated severe storms remain possible this afternoon from parts of the Southeast and central/southern Appalachians to the Texas/Louisiana Gulf Coast. Some tornado threat may still develop across the Florida Peninsula by this evening, in association with Hurricane Helene. ...20Z Update... The only changes made to the Day 1 Convective Outlook were to trim thunder and severe contours across the Gulf Coast into the OH Valley, where lightning and strong wind gust coverage should become increasingly sparse through the day. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 09/25/2024 .PREV DISCUSSION... /ISSUED 1143 AM CDT Wed Sep 25 2024/ ..Southeast and southern Appalachians... The influence of the upstream mid/upper-level trough and moisture streaming north from the Gulf of Mexico and Helene will lead to widespread precipitation across parts of the Southeast and southern Appalachians. This will tend to limit available buoyancy in some areas, but strong to locally severe storms may occur. Favorable deep-layer winds/shear exist, especially across the southern Appalachians vicinity where a few semi-discrete supercells could occur aside from more prevalent quasi-linear convective bands. Locally damaging wind gusts and perhaps a tornado could accompany the strongest storms, before low/mid-level lapse rates and buoyancy become increasingly weak with time, and an outflow-reinforced effective front sags southward across the region. ...Texas Gulf Coast/Middle Gulf Coast... Somewhat stronger diurnal destabilization will be possible from parts of central/east Texas into Louisiana, and perhaps into Mississippi, with MLCAPE potentially increasing above 1500 J/kg. Isolated to widely scattered thunderstorm development will be possible near a southward-moving cold front. Effective shear will generally range from 25-35 kt, and a few modestly organized storms are possible. Isolated damaging gusts could accompany the strongest storms within this regime. ...Florida Peninsula and Keys... Hurricane Helene's wind field is forecast to be rather large, especially on the east side of the circulation, associated with a strengthening Helene through the afternoon and tonight. Reference the National Hurricane Center for the latest Helene details. This scenario will result in modestly strengthening low-level shear/SRH across the Florida Peninsula during the day, but more so into the evening and overnight after the peak diurnal instability cycle. Instability will likely remain rather weak overall, and details regarding the intensity of any outer rain bands remain uncertain. However, some tropical-cyclone tornado threat could evolve across parts of the Florida Peninsula and Keys, mainly into tonight. ...Eastern Washington/northern Idaho/northwest Montana... While buoyancy is expected to remain quite weak, relatively steep mid-level lapse rates will support thunderstorm potential late this afternoon through early evening from eastern Washington into northern Idaho and northwest Montana, in advance of the approaching shortwave trough. Strong deep-layer flow/shear could support a locally severe storm or two with gusty winds and possibly some hail. Read more

MD 2108 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHWESTERN VIRGINIA AND THE WESTERN CAROLINAS TO CENTRAL GEORGIA
Mesoscale Discussion 2108 NWS Storm Prediction Center Norman OK 0226 PM CDT Wed Sep 25 2024 Areas affected...southwestern Virginia and the western Carolinas to central Georgia Concerning...Severe potential...Watch unlikely Valid 251926Z - 252130Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong storms -- a few of which reaching severe levels -- are expected near and east of the higher terrain of the Appalachians. All-hazards severe risk -- including a brief tornado or two -- will be possible with the strongest of these storms, but coverage of the more substantial convection may preclude the need for WW issuance. DISCUSSION...Latest visible satellite imagery shows high cloudiness expanding across the pre-frontal warm sector at this time, though until now, ample heating has resulted in modest destabilization (around 1000 J/kg mixed-layer CAPE) near and just ahead of the slowly advancing cold front. Convection continues to gradually increase across the area, with one particularly organized storm now affecting the Habersham/Rabun County Georgia area, and -- soon -- portions of Oconee County South Carolina. The somewhat modest warm-sector CAPE is being partially offset -- in terms of potential for robust convection -- by relatively strong southwesterlies at mid levels southeast/east of the upper low near the confluence of the Ohio and Mississippi Rivers. This flow, atop low-level southeasterlies, is providing shear sufficient for both mid-level and -- to some degree -- low-level rotation. Though overall coverage of the more robust storms is expected to remain limited, the area bears watching given the favorable kinematic environment. While current expectations are that a WW will not be required, we will continue to monitor convective evolution and possible/additional destabilization this afternoon. ..Goss/Guyer.. 09/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RAH...RNK...CAE...GSP...MRX...FFC... LAT...LON 32858455 35038307 37168089 36938007 35928020 33098306 32678379 32858455 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...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 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...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 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...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 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...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 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...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 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...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 0248 PM CDT Wed Sep 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 09/25/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Sep 25 2024/ ...Synopsis... Fire weather concerns are expected to be low on Thursday. Hurricane Helene will be absorbed into the upper-level flow across the eastern US with widespread rainfall anticipated. Across the central and western US, a ridge of high pressure will remain in place with generally light winds. As such, no overlap of critically dry fuels with Elevated/Critical conditions is expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 PM CDT Wed Sep 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL APPALACHIANS INTO THE CAROLINAS AND SOUTHERN VIRGINIA... ...SUMMARY... A risk for a couple of tornadoes and damaging thunderstorm wind gusts exists from the central Appalachians into the Carolinas and southern Virginia. ...Synopsis... Upper ridging centered over the Southwest/northern Mexico is forecast to remain in place on Friday, with some modest northward expansion possible. To the east of this ridging, complex interaction is expected between a cold-core upper low initially over the Mid-South and Tropical Cyclone Helene, which will likely be centered over northern GA. Strong westerlies will remain along and north of the US/Canada border, and stable conditions will persist west of the Mississippi River. As such, tornadoes and strong convective gusts associated with Helene will constitute the only severe risk across the CONUS on Friday. ...Central Appalachians into the Carolinas and southern VA... Strong low to mid level flow will persist throughout the eastern periphery of Helene on Friday, over an area characterized by low to mid 70s dewpoints and modest buoyancy. This modest buoyancy could support some deeper convective cores, particularly within any rainbands. The combination of deeper, more persistent updrafts with the strong low to mid level flow could support strong, convectively augmented gusts and/or a few tornadoes. ..Mosier.. 09/25/2024 Read more

5-Day Uncertainty Track last updated Wed, 25 Sep 2024 17:52:27 GMT


Wind Speed Probabilities last updated Wed, 25 Sep 2024 15:28:45 GMT

Issued at 1200 PM CST Wed Sep 25 2024 000 WTPZ35 KNHC 251752 TCPEP5 BULLETIN Tropical Storm John Intermediate Advisory Number 11A NWS National Hurricane Center Miami FL EP102024 1200 PM CST Wed Sep 25 2024 ...JOHN STRENGTHENING... ...HURRICANE WATCH AND TROPICAL STORM WARNING IN EFFECT FOR SOUTHERN AND SOUTHWESTERN MEXICO... SUMMARY OF 1200 PM CST...1800 UTC...INFORMATION ----------------------------------------------- LOCATION...16.5N 101.4W ABOUT 105 MI...170 KM WSW OF ACAPULCO MEXICO ABOUT 85 MI...135 KM S OF ZIHUATANEJO MEXICO MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...NNE OR 30 DEGREES AT 3 MPH...5 KM/H MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Watch is in effect for... * Acapulco to Zihuatanejo A Tropical Storm Warning is in effect for... * Punta Maldonado to Lazaro Cardenas A Hurricane Watch means that hurricane conditions are possible within the watch area, in this case within 12 hours. Preparations to protect life and property should be rushed to completion. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case within 12 hours. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 1200 PM CST (1800 UTC), the center of Tropical Storm John was located near latitude 16.5 North, longitude 101.4 West. John is moving toward the north-northeast near 3 mph (5 km/h). A slow motion to the north is expected later today. On the forecast track, the center of the system is forecast to approach the southern and southwestern coast of Mexico on early Thursday and be inland on Friday. Maximum sustained winds have increased to near 45 mph (75 km/h) with higher gusts. John is forecast to strengthen as it approaches the coast of southern Mexico on Thursday. Tropical-storm-force winds extend outward up to 150 miles (240 km) from the center. The estimated minimum central pressure is 999 mb (29.50 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Through Friday, Tropical Storm John is expected to produce additional rainfall amounts of 10 to 20 inches with isolated totals around 30 inches across the Mexican States of Guerrero, Oaxaca, coastal Chiapas, and coastal Michoaca. For a complete depiction of forecast rainfall associated with Tropical Storm John, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_ep5.shtml?rainqpf STORM SURGE: A dangerous storm surge is expected to produce coastal flooding near and to the east of where the center makes landfall. Near the coast, the surge will be accompanied by large and destructive waves. WIND: Hurricane conditions are possible along the coast within the hurricane watch area Thursday. Winds are expected to first reach tropical storm strength as early as tonight, making outside preparations difficult or dangerous. Preparations to protect life and property should be rushed to completion. Tropical storm conditions are expected to first reach the coast within the tropical storm warning area as early as tonight. SURF: Swells associated with John are forecast to continue to affect the coast of southern Mexico through the week, with the potential for dangerous surf and rip currents. Please see local statements for more information. NEXT ADVISORY ------------- Next complete advisory at 300 PM CST. $$ Forecaster Bucci/R. Zelinsky

...JOHN STRENGTHENING... ...HURRICANE WATCH AND TROPICAL STORM WARNING IN EFFECT FOR SOUTHERN AND SOUTHWESTERN MEXICO... As of 12:00 PM CST Wed Sep 25 the center of John was located near 16.5, -101.4 with movement NNE at 3 mph. The minimum central pressure was 999 mb with maximum sustained winds of about 45 mph.