Tag Archive for: elsa

Elsa Upgraded to Hurricane

A USAF mission into Elsa along with radar data and surface observations from Barbados indicate that Elsa is now a hurricane. However, uncertainty remains about the storm’s track and intensification.

Elsa in the center of the image is skirting the northern coast of South America and about to cross over the windward islands. Note the small core near the center.

Just yesterday, the NHC showed Elsa remaining a tropical storm all the way to Florida. Now, the National Hurricane Center shows hurricane conditions are quickly spreading into the Windward Islands. Various watches and warnings are in effect for portions of the Caribbean Islands (See graphic below).

86 MPH Winds Reported

According to Jeff Lindner, Harris County’s meteorologist, Elsa has taken advantage of favorable conditions in the last 24 hours. Both the Air Force and land observers reported sustained winds of 86mph this morning. That makes Elsa a hurricane. Radar indicates good banding features and a small, central core.

Elsa continues to race WNW near 30mph which is extremely fast for a hurricane.

However, the system has thus far kept its low- and upper-level centers aligned.

Track

A strong sub-tropical ridge of high pressure to the north of the hurricane, will influence the track for the next 48 hours. Then Elsa will approach a weakness in the ridge and the forecasts become more uncertain.

One model shows the storm nearly dissipating over the Dominican Republic by Sunday. However, others show Elsa turning more north. Increasingly, this appears to be the more likely outcome. However, the spread is very large from east of the Bahamas to near the northern Yucatan at days 4-5 so confidence remains lower than average on the track.

Two models show Elsa making a beeline toward the central Gulf, but most take it east.

Intensity

Conditions seem favorable for increasing development. But the fast forward motion of Elsa could become a negative factor. Models show a large spread in intensity guidance, but most keep Elsa near the intensity it is now. As it approaches the Gulf, it should be a strong tropical storm or weak hurricane, but some forecasters see it growing much stronger.

NHC continues to lean toward the lower end of the guidance spectrum, but continues to indicate that Elsa could become stronger than forecasted – especially over the NW Caribbean Sea early next week.

Keep one eye on the Gulf. For the latest updates, check the National Hurricane Center.

Posted by Bob Rehak on 7/2/2021 at 8:30 am based on information from the NHC and HCFCD

1403 Days since Hurricane Harvey

Tropical Depression 5 Becomes Tropical Storm Elsa Overnight

In its 5 a.m. Thursday update of the Atlantic Basin, the National Hurricane Center upgraded tropical depression 5 to Tropical Storm Elsa.

Elsa is the earliest-known fifth named storm on record for the Atlantic basin in the satellite era (1966-present), breaking the record formerly held by Edouard on July 6, 2020.

Notice the beginning of an eye in Elsa at the 5 o’clock position and slight rotation.

Eastern Gulf Probabilities

At 5 a.m. Thursday 7/1/2021, forecasters believe that the eastern Gulf has up to a 30% chance of experiencing tropical-storm-force winds by late this week or early next.

The tropical cyclone’s cloud pattern became a little better organized overnight. Convective banding features are becoming more evident over the western and southwestern portions of the circulation.

Upper-level outflow is well-defined to the west of the system, and restricted over the eastern semicircle. The current intensity is 35 knots, making the cyclone a tropical storm.

The storm has been accelerating westward overnight, and the initial motion is around 22 knots. A strong subtropical ridge should steer the system quickly to the west-northwest for the next 3 days or so. However, there is significant uncertainty in the track forecast from days 3-5.

Disagreement Among Models, High Uncertainty

The ECMWF model turns the cyclone northward after interacting with Hispaniola while the other models such as the GFS, HWRF, and U.K. Met take Elsa across western Cuba and into the southeastern Gulf of Mexico. The official forecast is similar to the previous one last night. However the discrepancy in the models makes confidence in this track lower than usual.

Some intensification is likely for the next day or two, since Elsa is expected to be in an environment of warm sea-surface temperatures, fairly low vertical wind shear, and high mid-level relative humidity.

However, potential interaction of Elsa with the mountainous land masses of the Greater Antilles later in the forecast period could disrupt the circulation somewhat. Therefore the official intensity forecast, like the previous one, is quite conservative.

Key Messages

  1. Tropical storm conditions are expected beginning early Friday in portions of the Windward and southern Leeward Islands.
  2. Heavy rainfall from the system will move quickly across the Windward and southern Leeward Islands, including Barbados, on Friday. Isolated flash flooding and mudslides are possible.
  3. There is a risk of wind and rainfall impacts in portions of the Virgin Islands, Puerto Rico, Hispaniola, Cuba, the Turks and Caicos and the southeastern Bahamas through early next week. Interests in these areas should monitor the system’s progress and updates to the forecast.
  4. Interests in Florida should monitor updates to the forecast for this system, but it is too soon to determine what if any impacts could occur there next week given the uncertainty in the long-range forecast.

There is no forecast threat to the Houston area. Just beware in case you are traveling in the Caribbean or to Florida this week or next.

Posted by Bob Rehak at 6am on 7/1/2021 based on NHC information

1402 Days since Hurricane Harvey