Isaias and Rachel
Forecasts for both storms remain reasonably on track. Isaias intensified into a hurricane overnight, the first hurricane this season in the Atlantic Basin (and the latest date for a first hurricane on record). Isaias will likely intensify further (probably at least to a Category 2 status) and impact a portion of the northern Gulf coast region with damaging winds, dangerous storm surge, and heavy rain. Moisture from Isaias in combination with a northern stream system may produce significant rainfall across southern New England Sunday night into Monday. Rachel, or more precisely its remnants, may impact southern California and other portions of the Southwestern United States with flooding rains and gusty winds. More information on each storm follows.
Isaias
Isaias was intensifying rather rapidly this morning in a moist environment of light wind shear and over very warm waters. Further strengthening to at least a strong Category 2 status seems likely today. As Isaias approaches the northern Gulf coast, it will encounter increased wind shear and likely begin to weaken as well as become somewhat larger in size and more asymmetrical (with strongest winds to the east of the center). That weakening may be tempered some, however, due to the hurricane approaching a favorable entrance region of an upper-level jet. This kind of jet stream interaction has happened with past New England hurricanes. At any rate, Isaias is likely to approach the coast as a strong hurricane and then weaken more quickly after landfall.
Isaias was still moving to the ENE this morning but will fairly soon begin to make a more northward turn and begin to accelerate. A turn toward the northeast and north will take place as the storm comes under the influence of an approaching upper-level trough that sharpens over Texas to its west and a building upper-level ridge to its east. Although there remains some cross track spread in the various models, Isaias will likely make landfall somewhere in the Mobile/Pensacola area early Friday evening. People in that region should not focus on a precise track or landfall location but should make sure they are prepared for a plausible worst-case scenario (and be happy if they miss the brunt of the storm!).
Conditions will begin to deteriorate tonight and more rapidly deteriorate during Friday along the Mississippi, Alabama, and much of the Florida panhandle coastlines. Preparations need to be completed today in that region. The strongest winds and highest storm surge will occur along and to the right of the hurricane’s track. The highest risk of damaging winds (with associated power outages) and the storm surge (potentially a life-threatening 5 to 7 feet) looks to be along the coastline from the greater Mobile, AL area to Panama City, FL. Heavy rainfall of 4 to 6+ inches may occur along this portion of the Gulf coast and the adjacent Southeast United States with a risk of flash flooding in spots. There also is a risk of a few embedded short track tornadoes in the northeast quadrant of Isaias. Portions of the Mississippi, Alabama, and Florida panhandle coastlines remain under a Hurricane Warning.
After Isaias makes landfall, it should weaken fairly quickly late Friday night or early Saturday morning. The moisture-laden remnants of Isaias will move north along or a little east of the Mississippi Valley and then turn to the east along the Ohio Valley as the remnants interact with a northern stream upper trough. Those remnants are then expected to be embedded in an extratropical surface low pressure center that eventually passes near or somewhat south of the New England south coast on Monday. Rain is likely across southern New England Sunday night into Monday. How much rain will depend just how close the low center passes to southern New England.
Rachel
Rachel has encountered drier air and has weakened into a tropical storm. Although still moving toward the WNW, Rachel will be picked up by a fairly amplified mid to upper-level trough moving across the Pacific. This will result in Rachel turning to the northeast. This will bring Rachael as a weakening tropical storm or post tropical storm to northern Baja California. Rachel will continue to weaken as it moves over cooler ocean waters and encounters stronger vertical wind shear. Although Rachael may be losing its identity as it moves over northern Baja California (probably on Sunday), it will still bring areas of heavy rain (with a flash flood risk) and gusty winds to southern California and other portions of the Southwest United States.
Next Message
Will continue to monitor these two storms and issue follow-up messages if significant changes in the forecast occur. For more specific and most up to date information, interests should refer to the latest Advisories from the National Hurricane Center and applicable local National Weather Service forecasts/warnings for these storms.
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The National Weather Service monitors the weather 24/7 and updates forecasts, watches, and warnings as necessary. For most of southern New England, refer to your local Weather Forecast Office for the latest forecast/warning information at weather.gov/box. For information from other Weather Forecast Offices, go to weather.gov and click on the location of interest on the map. For the latest advisories on tropical cyclones, go to the National Hurricane Center.
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Message issued October 8, 2026 by:
Bob Thompson
Retired National Weather Service Meteorologist
Blue Hill Observatory and Science Center Advisory Council member
