Disturbance festering in southwestern Caribbean

For nearly a week now, there has been an area of disturbed weather in the extreme southwestern Caribbean.  It's origins appear to be a combination of a  tail of a cold front and the ambient monsoon depression.  There is a 1010mb Low associated with the disturbance, and the low-level center is approximately 200 miles off the Nicaraguan coast.

The system is in a low-shear environment, and the shear is expected to remain below 20kts for at least the next several days.  The SST is and will be nearly 30C.  There is not yet a lot of model guidance for this, but the global models indicate that it will develop and VERY slowly crawl northward toward Cuba as it intensifies.  Certainly something to keep a very close eye on, since the western Caribbean during time of year has birthed some infamous Category 5 hurricanes: Hattie 1961, Mitch 1998, and Wilma 2005.  The plot below shows the tracks of 11 storms that formed in October in the western Caribbean and became major hurricanes.  Note the relatively tight track pattern... north toward Cuba and Florida (Hattie, Mitch, and Wilma are the 3 that first went west before recurving/dissipating).  If named, the next name on the list is Rina (replaces Rita from 2005).

Please visit my tropical Atlantic headquarters.
Subscribe to get these updates emailed to you.

Philippe becomes a hurricane after 12 days

The first advisory was written on Philippe on Sept 24th, and since then, it has fluctuated in intensity from 35-60kts, but never dropped to a depression, and never made it to a hurricane... until this morning.  At 15Z today, Philippe's estimated intensity was 70kts and 985mb, making it the 5th hurricane of the season.  It's located about 415 miles southeast of Bermuda and moving NNE at 8kts.

However, this is also its last gasp as a tropical system.  Over the next couple of days, it will encounter SSTs nearing 20C and vertical shear up to 50kts and it will become an extratropical storm then finally merge with its mid-latitude trough.

To support the 70kt hurricane classification, the microwave image below (from NRL in Monterey CA... at 1023Z this morning) shows what appears to be an eye and eyewall, and definitely some strong tightly-curved rainbands.  The latest visible and infrared images are indeed showing a slightly clearing eye... I included an enhanced visible image from 1445Z below the microwave image so you don't just have to take my work for it!

Please visit my tropical Atlantic headquarters.

Ophelia turns extratropical, Philippe still a TS

At 15Z today, the final advisory was written for Ophelia... 18 days after it left the African coast and 13 days after it was first classified as a tropical storm.  Over the weekend, the storm reached a peak intensity of 120kts and 940mb (Category 4) as it passed 140 miles east of Bermuda.  It's presently a 50kt extratropical cyclone and just passed over Newfoundland (exactly the same landfall location as Maria 17 days ago!).

Early Saturday morning, it did indeed pass very close (just 5.4 miles west!!!) to Buoy 41049 as I mentioned.  The buoy reported 40ft waves, wind gusts up to 100kts, and a pressure of 952mb.  The plot below was made using hourly data from the buoy:

Philippe is still hanging around, and is still a tropical storm.  Surprisingly though, on Sunday morning, it was nearly a hurricane!  It reached an intensity of 60kts and 993mb, but has since weakened again to 55kts.

It is forecast to continue westward for another 24-36 hours, then recurve abruptly into the north central Atlantic.

Please visit my tropical Atlantic headquarters.