Atlantic Sat Image

Atlantic Sat Image
Clouds over Atlantic

Tuesday, May 31, 2011

Watching a low in the Caribbean

The map above shows an area of Low Pressure in the Southwestern Caribbean Sea. It will be status quo for this feature over the next few days .


Lets take a look at some items impacting this area.

  1. In its favor: The broad low is sitting over an area that is cliamatologically favored for development. It is also sitting over very warm water. As you know, the hotter the water, the more energy for systems to grow.

  2. Working against it: Strong upper level winds are keeping it in check and not allowing it to grow vertically.

The low will meander over the Caribbean at least through Friday. When it does begin to move, it will probably travel in a northeasterly direction pushing most of the rain over Jamaica, Eastern Cuba and Hispaniola. You may remember Haiti suffered greatly from tropical floods last year, they do not need a repeat of that. We in turn need the rain, but it will probably by-pass us altogether.

We will watch it just in case it tries to throw us a curve ball.

Monday, May 30, 2011

Early signs

This is the latest from the tropics. Notice the two Tropical Waves in the Caribbean Sea.

The first wave is in the Southeastern Caribbean impacting the coast of Venezuela with limited moisture. Strong upper winds will keep it in check.

The second is pushing into Northeastern Colombia with minimal shower activity. This one should be absorbed by the local wind pattern soon.

The most important feature we are following, is not even seen on the map above.

This one could consequently be of relevance to us. It is a huge area of disturbed weather over the middle of the Caribbean Sea. Latest observations indicate a possible broad area of low pressure in the Western Caribbean with plenty of moisture. Cloudiness and rain from this area extend all the way out to Hispaniola and even Puerto Rico.

Because high pressure is sitting over this area, a few long range models place some of that rain here later this week. High pressure directly over an area of low pressure is part of the recipe for a tropical system to develop. This is why NHC is suggesting further strengthening of the low with possible development in 36 to 72 hours.

Rain is also pushing out of the Caribbean and traveling Northeast impacting the Southeastern Bahamas as well as the Turks and Caicos islands.

The final item we are watching is an area of low pressure indicated by the "L", on the map. It is an upper low which in turn is pushing a few smaller surface lows along. In the long run this may develop into a full surface low but as of now it is not showing any signs of that. If it did grow stronger, upper level winds should keep it away from the Continental U.S.

Thursday, May 19, 2011

Hurricane outlook 2011

The new projections from NOAA have been issued and they show we could be in for another active season. Nothing new here, we've been seeing these types of outlooks now for over 15 years.

Last year was the third most active season on record. We were extremely lucky with no hurricanes making landfall, but don't let your guard down, only one storm made landfall across South Florida in 1992 and it was hurricane Andrew - a cat 5. It just takes one.

Here is the forecast for hurricane season 2011, which starts June 1st.

Expect 12 to 18 named systems out of which 6 to 10 could become hurricanes, and out of that number 3 to 6 could turn into major storms (Category 3 or above).

An average season shapes up like this: 11 named storms, six hurricanes and two major hurricanes.

The experts at NOAA give the 2011 forecast a 70% chance probability of panning out.

Gerry Bell, an expert with the National Hurricane Center goes out on a limb by saying we may be in for a rock-n-roll season. “In addition to multiple climate factors, seasonal climate models also indicate an above-normal season is likely, and even suggest we could see activity comparable to some of the active seasons since 1995.” I hope we don't see that kind activity.

Just remember what no forecast can ever tell us... where a hurricane will make landfall.

So why this outlook?

It appears we remain in the middle of a period of increased hurricane activity lasting about 25 years. This high activity cycle began in 1995. That year stands as the second most active season, with 2005 topping the list.

As you know, hurricanes need about 80° of ocean water temperature to develop . This year, Atlantic ocean water is running up to two degrees warmer-than-average and that could lead to more storms.

La NiƱa, which is a cooling of the Pacific Equatorial waters ( and helps hurricane formation ) continues to weaken, but its effects may stick around well into hurricane season.

Here are some other tid bits for you to ponder. Our instruments have improved hundredfold over last decade. They are able to detect smaller systems that NHC would not have classified as storms in the past. We can detect minute changes in the ocean's temperature and forecast with more accuracy than ever before,but still, mother nature holds back some of its secrets.

There is still a long way to go in forecasting how strong a hurricane will be. (Remember Charlie in 2004?) The science is not yet there, but experts are working on it.

Remember, I can never give you a forecast for an earthquake. If I can give you a 15 minute heads up on a tornado, I am really on my game that day.... but with a hurricane you will never be taken by surprise. Unlike all the other phenomena, you will be bored of seeing me on TV with warnings and advisories regarding a hurricane, sometimes up to a week in advance.

So prepare and you will be fine. Good luck and we'll ride through this hurricane season together.

Wednesday, May 4, 2011

Rainy Season Forecast

The National Weather Service issued their rainy season outlook this week and this is a summary of what they said.

NWS expects a slightly above average rainy season with most of the rain coming after July.

Because the ground is so dry,we are under an "Extreme Drought" so expect a High Fire risk until then.

A Neutral ENSO (Neither La Nina nor El Nino) is the main reason for this outlook, although they place "low confidence" on the forecast. NWS is also counting on at least one tropical system to make up for the deficit.

FYI:The average rain deficit for our dry season during a LA NINA year is about 4". The 2010-2011 season has seen around a 16" deficit.

Average precip for rainy season is 44". This is about 70% of the annual amount.

The Criteria for rainy season is three consecutive nights of above 70° temps and dew points, with daily t-storms.

Average Start date of the rainy season is May 20-27th. Average end is October 17th.

Monday, May 2, 2011

Tornado Tragedy is a Record

Last week, the nation's mid section got hammered by a strong line of merciless super cell thunderstorms. The net result was a line of tornadoes that killed over 300 people. Today, the National Weather Service informs us that this is a record setting event.

According to AP: Preliminary government estimates say there were more tornadoes in a single day last week than any other day in U.S. history.

Government analysts said Monday there were 362 tornadoes during last week's outbreak, including a record-setting 312 in one 24-hour period.

The National Oceanic and Atmospheric Administration said the largest previous number on record in one event occurred from April 3-4, 1974, with 148 tornadoes.

NOAA says 340 people were killed during the 24-hour-period from 8:00 a.m. Wednesday to Thursday.

It was the deadliest single day for tornadoes since the March 18, 1925, tornado outbreak that had 747 fatalities across 7 states.