{ "number": 700, "headline": "August 12, 2025 Tuesday Tropical Storm Erin", "standfirst": "Erin remains weak but should intensify into a hurricane by Thursday", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-08-12", "published": "2025-08-12T14:56:14.252000Z", "updated": null, "access": "free", "body_html": "
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2025 Atlantic Hurricane Season [Day 72]. My FORECAST for this year is 14 named storms, 7 hurricanes, and 3 majors.

2025: 5 named storms, 0 hurricanes, and 0 majors

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Monday Evening Tropical Update

  1. Tropical Storm Erin (05L) over the eastern Atlantic

  2. Additional tropical waves are following Erin \u2014 at lower latitudes, so more concerning if one of these \u201ccatches fire\u201d in the MDR or down the road in the Caribbean, Bahamas, or Gulf of Mexico.

Good morning! Tropical Storm Erin is racing westward across the Eastern Atlantic over cool ocean waters. There is minimal convection or shower activity due to the dry environment at this latitude + cool SSTs. However, the overall environment should moisten over much warmer water in the coming days allowing for steady intensification into a hurricane \u2014 then Major Hurricane in 4-5 days.

It is too soon to discount \u2014 or pinpoint \u2014 USA landfall impacts from Erin (05L) but based upon current model guidance \u2014 the chance RIGHT NOW remains low < 10%.

Weather model errors are > 300 miles at Days 7-10+ for tropical storms and hurricanes so that is a HUGE cone to be drawn on any map points. However, as the Lower 48 comes into view of Erin in the next few days, our models will become more confident/certain on the eventual outcome \u2014 so we should know on Thursday what will happen.

Welcome to visitors and thank you to subscribers \u2014 your support is appreciated. A year ago, I didn\u2019t think I would be particularly good at producing a weather newsletter, but hopefully it provides value and entertainment alike. New annual subscribers can receive 30% offer. Sharing / liking + commenting helps this newsletter\u2019s promotion within the Substack ecosystem.

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ECMWF 06z | Precipitable Water Next 6-days

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My favorite parameter: through the next 6-days from most recent 06z forecast \u2014> Erin dips southward and then WNW w/973 mb pressure (Category 2) east of the Bahamas. Two more tropical waves are following Erin.

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Ridge strength at Day 8 \u2014 588-590 dm

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Hurricanes are out of balance with the surrounding tropical environment and want to escape (head poleward). However, ridging in the subtropics usually prevents northward movement but instead a WNW drift \u2014 slowly gaining latitude over many days.

We\u2019ll be watching the intensity of the subtropical ridge to the north of Erin \u2014 with 588-590 dm matching the outermost closed contour of the circulation to match up with the Bermuda High / subtropical ridge.

ECMWF 00Z | Integrated Vapor Transport Next 12-days | Atlantic Basin

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+Moisture transport vectors from the 12z flagship solution. The ECMWF 00z control shows a East Coast \u201cclose call\u201d similar to Erin (2001) almost 25-years ago BUT another system on its heels that would be westward moving as the ridge builds behind Erin. More waves come off Africa into Week 2 (August 22)

ECMWF 00z Simulated Satellite | Water Vapor

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The middle latitude circulation \u2014> troughs are coming off North America constantly \u2014 and it seems likely that Erin will easily break through a weakness in the subtropical ridging to recurve northward. Once it reaches the latitude off the Carolinas, dry air + impacts of jet stream / trough will expand the wind field drastically \u2014> massive system off the East Coast. At Day 7: Erin should be near its initial peak intensity of Category 4+

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Atlantic Basin Outlook

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Tropical Storm Erin (05L) up to 95 knots (almost major hurricane) in 4-days

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Erin will be moving quickly over warm water soon > 26\u00b0C

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Atlantic Satellite Imagery | Infrared

Trough in Gulf is firing showers but no development expected (0%)

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Tropical Storm Erin | Low level swirl

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Eastern Atlantic & Tropical Africa | Satellite Image

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Another tropical wave emerged off the Africa coast earlier today but hasn\u2019t maintained its convective vigor. Upstream \u2014 another wave moves out of Nigeria.

NASA GEOS-5 | 00z DUST Aerosol Optical Depth | 8-day Forecast

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Plumes of Saharan dust coming off African continent to north of tropical wave and monsoon trough/ITCZ and any tropical waves must contend with this negative influence on its trek westward across the Atlantic MDR.

Atlantic Ocean Surface Temperatures (SST) + Anomaly (vs. last 20-years)

NOAA Tropical Surface Analysis | 06z

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Atlantic Tropical Waves =1

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Tracks of Tropical Storm Erin (05L) | ATCF

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We watch the HCCA (Corrected Consensus) product from NHC \u2014 and it is on the WESTERN edge of the guidance envelope \u2014> important for track changes at 12z.

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EPS Ensembles (00z) Full Physics (3 ensembles = 6%) landfall impact

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Looking into Day 14 \u2014> Scattered development from following tropical waves.

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AIFS-ENS (06z) Machine Learning \u2014 a few more outlier landfalls ~10%

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Following waves at Day 14 \u2014> development

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Previous 00z AIFS-ENS | Tropical Storm Erin (looks quite similar to 06z)

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ECMWF AIFS-Single 06z Cycle \u2014> Erin offshore at Day 9

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Gulf system at Day 15 \u2014> just keeping an eye again for consistency (no action to take)

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NOAA GFS 06z | Out to Sea \u2014> Erin

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GEFS Ensembles 06z | All Tracks through Day 8 | Ensemble Mean is very close to GFS \u2014> Out to Sea

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Intensity of Erin from HAFS-A and HAFS-B \u2014> Category 1 in the next 5-days \u2014 less vigorous intensification than previous forecasts

Eastern and Central Pacific Tropical Update

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Henriette is still a tiny hurricane well north of Hawaii.

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Rest of Eastern Pacific QUIET for the next 7-days

Western Pacific Typhoon Update

Typhoon Podul (16W) may become a major hurricane strength storm before landfall over southeast Taiwan in next 18-hours.

Ryan\u2019s notes from August:

Heading into mid-August with a more active period in the Atlantic basin \u2014> remember that we have many models updating every 6-12 hours, and many show catastrophic or historic solutions e.g. major hurricanes near land including the U.S.

HOWEVER, nothing is imminent or set in stone. We only use models to show the \u201cplausible\u201d scenarios of systems that could/may develop. We have 100s of solutions generated daily \u2014 1000s per week. Digesting this information is the job of responsible meteorologists and media \u2014 to process the data, assess the risks, and add value.

The models cannot consistently and/or skillfully look over the predictability horizon e.g. 8-10 days especially with tropical cyclones. The convection / storm clusters are not resolved by the full physics weather models at their current resolution (9 km to 25 km). Also, the A.I. models do not provide that much of an additional skill gain for individual tropical cyclones that have not yet formed.

As we watch tropical waves come off Africa in the coming days, each/every has the potential to develop especially heading into August. However, when/where and what impacts are unknown.

Maps sourced from weathermodels.com designed and innovated by yours truly! Please subscribe there for real-time access to the newest maps, charts from all of the weather models including ECMWF.

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2025: 5 named storms, 0 hurricanes, and 0 majors

Tropical Storm Erin (05L) over the eastern Atlantic

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