Monday, June 25, 2012

Debby weaker, but not moving

Tropical Storm Debby is a little weaker this Monday and staying put in the northeastern Gulf of Mexico.  The center is about 100 mi Southeast of Pensacola, but there is very little rain there, most of the activity is to the east.

Our impacts will be from that tail of clouds that extends from Central Florida southeast to the Yucatan Peninsula.  It will continue to draw moisture our way and cause anytime downpours.

This is a great example of how much trouble even a weak Tropical Storm can cause. Heavy rain and flooding has been reported across Central and Northern Florida.  We have seen our fair share of strong storms due to Debby.


The latest:

  • Debby is now away from the hottest area of the Gulf of Mexico, which means it should not grow any stronger.
  • Having said that, as long as the center remains over water, it has a chance for intensification, or at least to remain as a storm a few more days.

Where will it go?

  • This what NHC says:     BEST GUESS AT INITIAL MOTION IS QUASI-STATIONARY.  
  • The reason for this uncertain outlook is because Debby is stuck between 2 high pressure systems and until they move, Debby will stay put.

The cone of uncertainty now includes parts of South Florida. This has so far been one interesting storm to track.



The models are finally getting a better idea. The best projections right now call for some strong upper winds to dive out of the northeast and finally push Debby out into the Atlantic. That may not happen for 3-5 days.





Stay tuned for the latest

Sunday, June 24, 2012

Debby, Now Florida Worry

As we mentioned Sunday morning, NHC hinted at the possibility of a cone shift, and now with the latest advisory, it has happened.  Debby is less of a worry for Louisiana and more of a threat for Northern Florida.



NHC says the new cone is a compromise of all the different models and solutions over the last 24 hours. The GFS model has been consistent with moving the tropical storm East, while the ECMWF , and others, kept it heading West.  As of the latest run, more and more models are coming in line with the thinking that Debby will meander North over the next few days before moving Northeast.

NHC is not completely comfortable with the outcome of the new model runs, they say, "THE NEW OFFICIAL TRACK REMAINS A LOW-CONFIDENCE FORECAST."










What is happening now with Debby?:

  • Latest recon suggests it is not getting any stronger due to strong upper winds keeping it in check.
  • Those winds are not expected to weaken over the next 3 days. However, it is sitting over very warm waters and that could lead to a chance for strengthening.
  • Most of the rain and wind remains to the east of the center impacting mostly Florida. 
  • Advisories are in effect from Englewood Florida on the West Coast, north through the Alabama/Mississippi border.

Locally our weather pattern will remain a mess
  • Plenty of rain to the Southwest continues to aim for us
  • Could still see pockets of heavy rain through the overnight
  • NWS says: ISOLATED SEVERE AND TORNADIC STORMS CANNOT BE RULED OUT THROUGH THE NIGHTTIME HOURS.
  • Plenty of moisture will hang around over the next few days with more heavy rain possible through Wednesday.



Troublesome Debby

Tropical Storm Debby is proving to be a challenge for forecasters at the National Hurricane Center.The satellite picture shows a system sheared by upper winds with most of the rain and winds over Florida.

Experts are unsure of where Debby may end up and are telling us to be on the lookout as the cone may change at any time.

Heavy rain is moving across Western Cuba, the Straits, the Bahamas, and of course from the Keys through Tampa. Some of this activity could turn severe on Sunday.

Tornadoes can pop up anywhere across South Florida over the next 24 hours.


What is going on with Debby?

  • Strong upper winds are keeping the rain on the eastern half of the storm
  • These very same upper winds will keep Debby from getting stronger for another 24-48 hrs
  • All the rain on the eastern side is impacting South Florida with Foul Weather.



The latest forecast cone has Debby moving very little in the days ahead and possibly becoming a Hurricane just Southeast of Louisiana by Wednesday.  But this remains uncertain. This is due in part to the models still not being in agreement as to where Debby may end up.

Watches and Warnings have been extended to include parts of Florida's West Coast.

Debby is presently moving northeast and impacting Florida more than Alabama, Mississippi, or Louisiana.







The latest model runs still show an uncertain future with many possible tracks and directions.

As of Sunday morning this is what NHC is saying:
"IT IS A VERY DIFFICULT AND HIGHLY UNCERTAIN FORECAST"

What is the forecast
Even NHC, is having a bit of a problem with this system.  "THE TRACK FORECAST IS EVEN MORE COMPLEX"


According to one model the GFS, the strong upper level winds blowing west to east over the Southeastern US, should absorb Debby and push it Northeast.

The GFS, ECMWF, and HWRF models, suggest a high pressure system developing around Georgia and pushing Debby to the West.

Because of all this insecurity, the cone may change at any time. NHC goes on to say:
'WE MUST BE READY TO MAKE A CHANGE OF THE FORECAST TRACK
AT ANY TIME"



Local Impacts:


Because of Debby, we will remain in a very unstable pattern. This is what the local NWS is saying:

DEBBY WILL BRING AT LEAST WEAKLY ORGANIZED FEEDER BANDS THROUGH
THE AREA. ISOLATED TORNADOES COULD EASILY FORM WITH THE MORE
CELLULAR STORMS WITHIN THESE BANDS. IN ADDITION, A FEW
THUNDERSTORMS COULD CONTAIN VERY HEAVY RAINFALL AND GUSTY WINDS
OF 50 TO 55 MPH. OVERALL, THE SHORT TERM FORECAST IS ON TRACK,
WITH JUST MINOR ADJUSTMENTS TO ACCOUNT FOR THE LATEST TRENDS.







Saturday, June 23, 2012

Tropical Storm Debby

The National Hurricane Center has classified the Low in the Gulf of Mexico as Tropical Storm "Debby"

Here is the latest:

  • A recon mission Saturday morning was able to detect tropical storm force winds and a well defined center of circulation. 
  • Tropical Storm Advisories have been issued for the Louisiana Coast
  • Models remain uncertain as to where it may end up down the road.  There is no clear consensus... with some tracks pushing Debby East, others North, and most West/Southwest.




The Hurricane Center is going with the higher average of Debby taking a Westward jog.

This is the "Cone of Uncertainty" from NHC.



We expect this system to hover in the middle of the Gulf of Mexico through Sunday drawing plenty of moisture our way. We could see pockets of heavy rain anytime through Monday, maybe even until Tuesday.

This is what NWS is saying:


LOW PRESSURE WILL SLOWLY MOVE NORTH OVER THE GULF OF MEXICO THIS
WEEKEND. THIS FEATURE WILL TRANSPORT DEEP TROPICAL MOISTURE INTO
SOUTH FLORIDA THROUGH AT LEAST SUNDAY NIGHT WITH PERIODS OF HEAVY
RAINFALL POSSIBLE.

ADDITIONAL RAINFALL AMOUNTS THROUGH SUNDAY EVENING WILL LIKELY
RANGE FROM 1 TO 3 INCHES ALONG THE EAST COAST AND FROM 2 TO 4
INCHES ALONG THE WEST COAST. AS TYPICALLY OBSERVED DURING THESE
EVENTS, LOCALLY HIGHER AMOUNTS ARE POSSIBLE SINCE PERSISTENT
BANDS OF HEAVY RAINFALL MAY IMPACT A FEW AREAS.


Tropical Trouble

UPDATE: It appears the NAVY is already referring to the low in the Gulf as "Debby". We should see advisories by 5 pm

Here is the latest from NHC: We could have "Debby" soon in the Gulf.

BUOY OBSERVATIONS...SATELLITE DATA...AND PRELIMINARY
RECONNAISSANCE DATA INDICATE THAT A TROPICAL STORM
MAY BE FORMING IN THE CENTRAL GULF OF MEXICO ABOUT
250 MILES SOUTH-SOUTHEAST OF THE MOUTH OF THE
MISSISSIPPI RIVER.  IF THE PLANE IS ABLE TO IDENTIFY A
WELL-DEFINED SURFACE WIND CIRCULATION...
THEN ADVISORIES WILL BE INITIATED LATER TODAY.
HEAVY RAINS AND LOCALIZED FLOODING ARE POSSIBLE ACROSS
WESTERN CUBA AND MUCH OF FLORIDA OVER THE NEXT DAY OR SO. 


A broad area of low pressure is coming together  around 275 miles South/southeast of
the mouth of the Mississippi River.   Here is the latest:
  • A near-by buoy detected tropical storm force winds
  • NHC could classify it as a depression or a storm soon.
  • They are giving this low a 90% chance of getting stronger over the next 2 days.
  • If it becomes a Tropical Storm, it will be called "Debby".


Keep in mind there is plenty of heat energy over the Gulf waters to provide this system
with plenty of fuel.  Everyone along the West Coast of Florida should monitor this
closely. Watches and Warnings may be issued at any time.



As the low continues to get better defined, it will start wrapping more and more moisture around it's center. All that rain has to go through Cuba and South Florida first.  This will make for a soggy weekend. We may see on and off flood watches through Sunday night, so please drive carefully. The ground is already saturated and any additional rain will quickly overwhelm drains and flood streets.

If it develops, where is it headed? 
The models have been all over the place. They continue to fan out, some pushing the system  east  and others west. When they do this, it means they do not have a good handle on what is happening in the atmosphere and thus, they are having a harder time determining what may happen next. We just need to watch and wait. 






What can we expect?
This is what the local NWS office is saying:

LOW PRESSURE WILL SLOWLY MOVE NORTH OVER THE GULF OF
MEXICO THIS WEEKEND. THIS FEATURE WILL TRANSPORT DEEP
TROPICAL MOISTURE INTO SOUTH FLORIDA THROUGH AT LEAST
SUNDAY NIGHT WITH PERIODS OF HEAVY RAINFALL POSSIBLE.
ADDITIONAL RAINFALL AMOUNTS THROUGH SUNDAY EVENING
WILL LIKELY RANGE FROM 1 TO 3 INCHES ALONG THE EAST COAST
AND FROM 2 TO 4 INCHES ALONG THE WEST COAST. AS TYPICALLY
OBSERVED DURING THESE EVENTS, LOCALLY HIGHER AMOUNTS
ARE POSSIBLE SINCE PERSISTENT BANDS OF HEAVY RAINFALL MAY
IMPACT A FEW AREAS.







Friday, June 22, 2012

Next System?

Over the last 7 days, we have been monitoring a large batch of clouds and rain hovering through the Caribbean. At times, this brought us copious amounts of rain leading to localized street flooding.  This disturbance is apparently now taking shape close to the Yucatan Peninsula.



Pressures continue to fall in this area and at the same time, the low is keeping the moisture flow coming in from the South/Southwest. All the associated rain is expected to get dragged over us during the weekend making for a very soggy Saturday and Sunday.

Models show total rainfall for that period between 3-5 inches for Palm Beach, Broward, Miami-Dade and the Keys. As high as 7" by Collier and Mainland Monroe.

The National Hurricane Center is giving this feature an 80% chance it could become a depression or a tropical storm over the next 48 hours. If it becomes a tropical storm, it will be named "Debby".

The Hurricane Hunter mission for Friday was scrubbed. Another is on stand-by on Saturday if need be.


If it develops, where is it headed? 
The models have been all over the place. Early runs on Thursday showed this feature moving towards Mexico, then... late changes Thursday night pushed the low back to Florida.  On Friday, the models are fanning out. When they do this, it means they do not have a good handle on what is happening in the atmosphere and thus, they are having a harder time determining what may happen next. We just need to watch and wait. These runs provided by SFWMD.








If it heads to South Florida, what can we expect?
This is what the local NWS office is saying:


THE ONLY AFFECTS IT APPEARS FOR S FL WILL BE LONG SPELLS
OF AN ABUNDANCE OF CLOUD COVER AND PERIODS OF RAIN AND A 
FEW THUNDERSTORMS. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE 
WITH THE HEAVIER SHOWERS AND STORMS, AND THESE COULD SET UP 
JUST ABOUT ANYWHERE.


It will take a day or so for this "Low" to develop. Keep in mind there is plenty of heat energy over the Gulf waters to provide it plenty of fuel. If upper level winds, keeping it in check right now relax, it will open the door for possible rapid growth. Everyone along the West Coast of Florida should monitor this closely.


Wednesday, June 20, 2012

What a mess!

Over the last few days I have been following a huge pool of tropical moisture in the Caribbean Sea. This has lead to heavy downpours across Cuba, with flooding reported in the central part of the island. Now, all this rain has arrived here and it could stick around, on and off through, the weekend. (Maybe longer.)



This big mess of rain is expected to slowly move into the Gulf of Mexico, and once there, it could get caught up in strong upper winds and get sent back to Florida. Here is the thinking at NWS:

Models are in slightly better agreement with the evolution of this area of disturbed weather. The ECMWF model  is now agreeing with the GFS, depicting this Low pressure system getting absorbed by a disturbance in the mid to upper levels of the atmosphere .

This will then push the deepest moisture back to Florida, with the heaviest rain aiming for the Central and Northern part of the state.

Either way the wet pattern may be with us even into the early part of next week.




Because of all the heavy rain forecasted you can expect Flood Advisories to be issued at any time.

Meanwhile, NHC is also keeping their eyes on this area of disturbed weather. They say it has a medium chance for development.  You will also notice the tropical storm symbol in the Atlantic, this is "Chris" moving east with NO threat to land, only a worry for the shipping lanes.






Monday, June 18, 2012

Very long range models

If anything were to happen in the tropics this month, it would be either the Caribbean or Gulf of Mexico. Some very long range models hint at a few possibilities.

We are looking at the future tracks of a handful of systems developing in the region. On the following graph, the number on the left of the forward slash means what day the model is focusing on, while the number to the right is the time code.
  
  • NHC is already following one feature in the Western Atlantic, north of Bermuda. Even if this develops it will only be a worry for the shipping lanes.
  •  You can also appreciate how active the next few days may be if these models are right, with plenty of hot spots in the Caribbean and Gulf of Mexico.
  •  By the way, just because the models suggest something may brew, doesn't mean it will happen. This is just a heads up that the ingredients will be present in the atmosphere for a few systems to develop.
  •  NHC is not referencing any of these items yet but may start in the days ahead.

Saturday, June 2, 2012

Colorado State University changes forecast

Many commercial weather companies, universities, and of course the National Hurricane Center, issue a seasonal outlook.  At channel 7, we show Dr. William Gray's projections and NHC's.

The first because most people recognize him and his staff, at Colorado State University, as the best in the forecasting business. The latter because they are the ultimate authority when it comes to tropical systems.

But thats where similarities end.  While NHC stands firm with their outlook throughout the entire season, the CSU team updates their forecast frequently. They attribute this to long range changes in the sea/atmosphere environment and new "up to the minute" model runs.

Having said this, here is the JUNE 1st update. There will be a few more as the season progresses.

The average number of systems derived between the years 1981 through 2010 are as follows : 12 Named systems, out if which 6 hurricanes will develop, and out of these maybe 3-4 could reach category 3 or above.

Here is the update:
                              June 1st       April 4
                              Update        Previous        Average
Named systems        13*              10                   12
Hurricanes                5                 4                    6
Major Storms             2                 2                    3


*This number includes the 2 previous systems that popped up before the start of hurricane season. (Alberto & Beryl)

For the time being, everything is quiet in the tropics. Please prepare accordingly, it only takes one to make landfall.

Here is a link to a great article by NOAA showing their outlook and an explanation of how they reached their projections.

National Hurricane Center's 2012 Forecast