Invest 99 Changes Little

NHC is following a large wave with a weak low level circulation roughly 1150 miles west-southwest of the Cape Verde Islands. They are giving it a 20% chance it could grow stronger over the next few days as it moves west at a speed of 10-15 mph.

Here are the stats as of Tuesday morning. Lat: 9.3 N,  Lon: 39.6W, with top winds of  23 mph, and a pressure of  1010mb. Not that impressive, but it does have some showers and thunderstorms embedded along the low level center keeping it as an area worthy of watching.

Lets take a look at what is working for and against INVEST 99.

For:

• It continues to travel over warm waters that will provide more fuel for this tropical engine.
• Upper winds remain light so it should not encounter any major roadblocks in its possible development .

Temperatures are running in the low 80's along the Lat/Lon that Invest 99 is traversing.


Against:

• Still plenty of Saharan dust in the atmosphere that could absorb all of its moisture and dry it out

Everyone throughout the Caribbean Basin should watch this feature closely as it could impact the area in a few days. Most models now take the possible system through the Lesser Antilles, and into the Caribbean Sea where there is a good chance it could grow further.  These new runs keep it further south than they did on Monday when they showed it moving more towards the Bahamas.  We'll keep monitoring it.

New area to watch

The National Hurricane Center is watching an area of disturbed weather out in the Far Eastern Atlantic Ocean.

It is a weak tropical wave located about 800 miles Southwest of the Cape Verde Islands. This feature is producing showers and thunderstorms that could, in the long run, develop into something stronger. NHC is giving it a 20% chance for growth over the next 48 hours. NHC has deemed it an area worthy of further investigation and are now calling it INVEST 99L.

Right now the wave appears disheveled as it moves west, however, the Atlantic waters here are very warm so it will have enough fuel for growth. Upper winds appear weak and should not be a road block to the wave.

What is worrisome is the possible track this system could take if it develops. A series of early model runs suggest it could aim for the Lesser Antilles, then Puerto Rico and Hispaniola, followed by the Bahamas. It may end up impacting millions of people along its route.

All we can do right now is watch it carefully.

Climate Change

Just the mere mention of those two words and emotions will rise as fast as the temperatures this summer. It really doesn't matter if you believe it's a man-made problem or a natural earth cycle, it is here and we are feeling its wrath.

This is what the government says on the issue.

According to the EPA, the global average temperature increased by more than 1.4°F over the last century.¹ In fact, according to the National Oceanic and Atmospheric Administration (NOAA), the decade from 2000 to 2010 was the warmest on record, and 2010 was tied with 2005 as the warmest year on record. ² Rising global temperatures have also been accompanied by other changes in weather and climate. Many places have experienced changes in rainfall resulting in more intense rain, as well as more frequent and severe heat waves. The planet's oceans and glaciers have also experienced changes: oceans are warming and becoming more acidic, ice caps are melting, and sea levels are rising. ³ All of these changes are evidence that our world is getting warmer.

Experts say if the earth warms up an additional 3-4 degrees, it would be a change so dramatic, it could challenge our survival.

Lets take a quick look at some of the changes we have seen so far this year:

NOAA says, the last 12 months ending in June of 2012, was the warmest period since record-keeping began in 1895.

This record heat is responsible for the deaths of dozens of people, sky high cooling bills, and now possible sky high food costs.  About 64 percent of the continental United States was experiencing drought in July, with water supplies running dangerously low in some areas.  The heat is also taking a toll on agriculture which will lead to higher costs from cereals, to dairy, and beef.

You can also add the misery of bugs.
According to the National Pest Management Association (NPMA), the record heat is bringing out the ants, fleas, ticks, earwigs and black widows. These are a few of the pests making a strong showing this year. A spokesperson for the agency says, "Insects are cold-blooded, which means that their body temperatures are regulated by the temperature of their environment," NPMA public affairs officer Missy Henriksen said in a statement. "In cold weather, insects' internal temperatures drop, causing them to slow down. But in warm weather, they become more active. Larvae grow at a faster rate, reproduction cycles speed up, and they move faster."


Meanwhile, Greenland has lost most of it's ice cap, with 97% of the ice cover turning to slush. However, scientists say this may all be normal.

Every summer Greenland loses about half of its ice sheet, but this year its almost all gone. Scientist have been keeping tabs on the ice with satellites for a good 30 years. They say the meltdown was so extensive that scientists from NASA's Jet Propulsion Laboratory questioned if it was caused by some kind of malfunction with the equipment. The situation had to be confirmed independently by other climatologists.

This is what they found: By early July , according to the satellite information, 40 percent of the ice was melted. Four days later it was up to 97 percent, and even the area around the highest point of the ice sheet, Summit Station, showed signs of melting. At the same time, a ridge of warm air known as a heat dome was affecting the country, which likely had a lot to do with the melting.

But, this could be a natural cycle: A glaciologist from Goddard, Lora Koenig, also a member of the research team analyzing the satellite data, said in a statement: "Ice cores from the Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time."

Researchers don't know  if this will contribute to sea levels rising in Greenland, but if it happens again in the next few years, that could threaten the stability of the ice sheet, which would mean major cause for concern.

So whether you think this is all man-made or Mother Nature is going through her mid-life crisis, we are like fish in a fishbowl. We need to figure out how to keep our water clean or else.

NHC eyeing rain over us for possible development

All this rain over South Florida has sparked the interest of the National Hurricane Center.  Many areas have received between 1 and 2 inches, in the last 24 hours, and more can be expected over the next 2 days.

NHC is watching this area closely and, for the moment, are giving it a low chance for development. As of Sunday afternoon this area of clouds and rain has a 10% chance to grow stronger during the next 48 hours.

The area that NHC is focusing on extends from the NW Bahamas, South Florida, and the Straits. Heavy rain has been evident since early Sunday morning, with a wind gust of 62 mph reported at Fowey Rocks on Biscayne Bay.

For the time being, surface pressure remains high and upper level winds are still hostile for hurricane formation.

Even if this area of clouds and rain doesn't get any stronger, we can expect rounds of heavy rain through Tuesday. It should drift NW into the Gulf of Mexico and move towards the Panhandle.

Stay tuned for the latest developments.

Week ahead

Local:

There is plenty of moisture surrounding South Florida moving our way. We can expect a high chance for showers, t-storms, and even some torrential downpours through Tuesday.

By the middle of the week, some dust (swept into the atmosphere from the Saharan Desert), is expected to make its way across South Florida. This will make for beautiful sunsets and hazy skies, but will also be a worry for folks with respiratory problems.

The arrival of the African dust will also usher in warmer temps. Forecasts are calling for heat indices in the 100-105 degree range.

National:

Hot and humid conditions are making a reappearance in the Central U.S. and are expected to continue for the next several days.

Heat Advisories have been issued for portions of the northern Great Plains and Upper Midwest where high temperatures will easily top the triple digit mark. Daytime temperatures are forecast to be 15 to 20 degrees above average throughout the region.

In the Tropics:

Thankfully everything is quiet.

Wednesday Weather Flash

 Here is your complete weather update for Wednesday, July 11th.

Local:

• We are stuck between high pressure over the Bahamas and a weak disturbance across the Gulf of Mexico. Most of the wind flow will be off the Atlantic Ocean dragging in tropical moisture and dumping it across South Florida. Whenever these pockets of moisture move in, we will see the chance for rain, so expect on and off anytime showers/storms.

• There is a weak tropical wave across Hispaniola. If it holds, it may move in Wednesday night with a few showers and storms.

National Update: Watching 2 areas

• The first. A cold front is expected to move over Montana early in the day, and across the Dakotas by nightfall. This should bring about the possibility of Severe Weather across that region.

• The second. Warm air will stick around from Texas through Georgia. This region could once again see strong storms by afternoon.

In the Tropics:

• Everything is quiet with only a few tropical waves moving East to West across the Atlantic. There is still some African dust floating across the Ocean keeping the atmosphere rather dry and not conducive for storm formation. The Bermuda High is still dominating and keeping conditions over the Atlantic very stable.

A Wave & African dust

A pesky tropical wave sliding to our South could bring us scattered showers through the weekend. Waves are very hard to forecast as they can grow quickly or fall apart just as fast. As this one moves over Cuba, we may get a few pockets of rain through Monday.

Most of the cloud cover with the wave remains over the Western Caribbean Sea. It will continue to head west over the next 24-48 hours.

You may have also noticed hazy skies over South Florida the last few days, NWS says this is due to dust that has traveled all the way from Africa and settled across the region. This is known as the Saharan Air Layer.  I know as someone who suffers from allergies, that this dust has not been kind to me, but there is hope. This what NWS is expecting:

• THE SAHARAN DUST THAT HAS BEEN PRESENT FOR THE PAST THREE DAYS IS BEGINNING TO CLEAR AS MOST OF THE DUST IS EXPECTED TO STAY SOUTH OF THE FLORIDA PENINSULA. HOWEVER...THE DEEP BLUE SKIES TYPICAL OF SOUTH FLORIDAWILL BE SLOW TO RETURN IN THE SHORT TERM.

By the way, the reason for the slow return of blue skies , will be lingering moisture from the wave to our South.

This dust helps make the sunsets redder and more brilliant. Its not only impacting us, but parts of the Caribbean as well. This is from NWS in San Juan:

• NAAPS AEROSOL MODEL INDICATING ANOTHER ROUND OF SAHARAN DUST MID NEXT WEEK.

There is some good news with this African dust, it actually helps to keep the air very dry. With arid conditions across the Atlantic, the chances for hurricanes to form remain low.

African dust emerges from the Saharan Desert as strong winds blow huge piles of sand into the atmosphere and get pushed west over the Atlantic Ocean.

Quieter Hurricane Season?

NOAA is reporting that sea surface temperatures in the Equatorial Pacific are rising. This is signaling the start of a natural phenomenon known as "El Niño".  This is a warming of the Pacific waters that not only affect marine currents, but atmospheric ones as well. It could impact weather patterns world wide.

This image illustrates in red, where the waters are warming near the equator throughout the Pacific Ocean.

This phenomenon was first discovered by fishermen from Peru decades ago as cold water fish would disappear from their coast due to the warming waters.  They called it "El Niño", because the warming would occur most often during Christmas, so they named it after the Christ child.

Throughout the world, heavy rain can be expected in normally arid areas, as well as drought conditions in typically wet places. Temperatures can fluctuate as well.


So what does this mean for us in South Florida?

• During El Niño years, vertical shear, or strong upper winds increase making it harder for hurricanes to form, and those that do, tend to be weaker.  
• Strong upper winds tend to keep most storms away from land.

If this pans out, it could be a more tranquil hurricane season. Lets keep our fingers crossed.

What do the official forecasts say?
Here is where it gets tricky. Models are split over the emergence of "El Niño".

• The dynamical models, including the NCEP Climate Forecast System (CFS), largely favor the development of El Niño by July-September 2012.  
• The majority of statistical models however, predict near normal sea surface temps in the Pacific through the end of 2012.

Experts are favoring the "El Niño" emergence later this summer. We will have to watch and wait.