Weather Blog: August 12, 2025 2 PM (Tropics)

NOW IS A GOOD TIME TO REVIEW HURRICANE PREPAREDNESS

Hurricane Preparedness

Tropical Storm Erin far out in the eastern tropical Atlantic as of Tuesday August 12 is a reminder that we are approaching the peak period of the hurricane season.  For those vulnerable to hurricanes, now is a good time to check and update their hurricane preparedness plans.  A hurricane preparedness plan need not be a formal document, but each family that could be vulnerable to hurricane impacts should have some plan of action should their area be threatened.  Vulnerability from hurricane impacts vary by location and may include flooding from storm surge, freshwater flooding from nearby streams/rivers, or wind damage depending upon the structural integrity of the home.  The action might involve evacuation if recommended or ordered by authorities, securing property such as propane tanks and/or outdoor furniture, ensuring a sump pump is in working order, moving property to a higher floor, etc.  Boatowners often need extra lead time, especially if it should be necessary to move their vessel to another anchorage or take it out of the water entirely.  A hurricane passing a relatively short distance offshore might have limited land impacts but still require boatowners to shore up moorings from peripheral winds and wave action.  The point is that all of us should consider actions we should take if threaten with a hurricane well before faced with a threat from a specific storm.  Whether or not Erin impacts any part of the United States coast, there will likely be additional tropical cyclones that form in the Atlantic Basin over the next couple of months or so.

Erin

Erin is expected to move westward to the south of an extensive subtropical ridge of high pressure and then likely turn more toward the west-northwest and northwest as it approaches a forecast weakness in the ridge.  It’s too soon to know if there will be any impacts on the U.S. east coast other than a potential increased risk of rip currents along the ocean side of the Cape and Islands sometime next week.  When looking this far out, meteorologists not only look at the various “operational” global models, but also their “ensemble runs.”  Each global model is run multiple times with slightly different initial conditions that interpolate various meteorological fields a little differently in the gaps between observations.  Keep in mind that those gaps in observations can be quite large over the oceans.

For now, the global operational models and the majority of ensemble runs depict Erin moving toward the southeast United States coastline and then recurving to the northwest, north, and northeast.  This recurvature track could keep Erin offshore of the United States coast as it is steered initially on the south side of a subtropical high-pressure ridge over the Atlantic but then on the west and northwest sides of that ridge.  Some ensemble runs recurve Erin close enough to the east coast for some fringe effects across Hatteras and the Cape and Islands while other ensemble runs keep Erin further offshore.  The future track of Erin is dependent upon the future strength and configuration of that subtropical ridge as well as any undulations in the mid latitude upper wind flow across North America and the northwest Atlantic.  Even the hurricane itself can influence its own steering to some extent depending upon its size, vertical extent, and intensity.  Thus, one needs to be very cautious in evaluating longer term projections of a hurricane track and account for what could be significant error given the dynamical nature of weather patterns.

Forecasting future intensity of Erin presents its own set of challenges.  Erin is presently in a low wind shear environment but with some mid-level dry air and only marginally warm sea surface temperatures.  As Erin progresses westward, it is expected to pass over warmer sea surface temperatures and remain in a low wind shear environment.  Thus, Erin is forecast by the National Hurricane Center to intensify into a hurricane in another day or two and possibly into a major hurricane (at least a category 3) in about 5 days.

Recommended Actions Regarding Erin

It’s too soon to predict whether Erin will impact any of the United States coastline.  It is not too soon to review how one might respond to any hurricane threat given we are approaching the usual peak time of hurricane season.  In addition, and more specifically regarding Erin, any mariners planning offshore trips next week should pay close attention to later forecasts from the National Weather Service and advisories from the National Hurricane Center.

Further Information

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 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 information on Atlantic basin hurricane activity, access the National Hurricane Center website at nhc.noaa.gov.

About this Blog and Disclaimer

These weather messages are issued when there is a potential risk of hazardous weather to southern New England, and they will provide background information regarding the significant weather with somewhat of an educational slant.  In the case of hurricanes, the author will attempt to issue a message when any portion of the United States coastline may be impacted.  It’s intended to complement and not serve as an alternative to official forecasts issued by the National Weather Service.  Readers are urged to check National Weather Service forecasts and warnings for the most timely and updated weather information.  This weather message is solely produced by the listed author and does not constitute an official product of the Blue Hill Observatory and Science Center (BHOSC).

The frequency of this blog will depend upon the nature of the weather threat and availability of the author.  Thus, for the latest information on weather forecasts and warnings, refer to the National Weather Service, which monitors and forecasts the weather 24/7.

Note that this specific weather blog was not issued due to an imminent hurricane threat but rather to remind people of the importance of hurricane preparedness before a specific and more imminent threat arises.

Blue Hill Observatory and Science Center (BHOSC)

The BHOSC maintains a continuous daily observation record that dates from February 1, 1885 without interruption and provides educational information on weather and climate to area students and the community at large.  Your support of BHOSC is much appreciated and enables this nonprofit organization to maintain the long-term climate record at the Blue Hill Observatory (longest continuous record in North America) and provide valuable educational resources on weather and climate via outreach to schools, site visits/tours, webinars, and conferences.  For more information on the Blue Hill Observatory and Science Center, explore bluehill.org.

Next Update on Erin

Since Erin is at least a week away from any possible United States impact, a follow-up message will not be issued for at least another day or two.

Message issued by:
Bob Thompson
Retired National Weather Service Meteorologist
Blue Hill Observatory and Science Center Board member