Ceaseless Wind

The Yucatan Peninsula may be the only inhibitor in getting three named tropical storms in the Atlantic Basin (Atlantic Ocean, Caribbean and Gulf of Mexico).

Late this morning, two hurricanes are churning out over the Atlantic, Igor and Julia.  Both storms seem fated to curve out over the open Atlantic over the next week or so.  Igor will be making Bermuda a bit nervous as it passes close to the island early Sunday morning.

A new tropical depression may be ready to form in the Caribbean.  But before it can develop the closed circulation and wind speed necessary to be the next named storm Karl, it will likely be disrupted by landfall on the Yucatan Peninsula.  It would have a shot at redevelopment on the other side of the peninsula.  In any event, it doesn’t look like a player for the mainland U.S

Igor Projection

This hurricane season has been active, largely as predicted by NOAA.  However, it does remind everyone that while the skill may exist for counting storms and gauging their intensity, forecasters still can’t tell you exactly where they may make U.S. landfall, if any ever do.  Moreover for the Ozarks, we would only be affected directly by storms which get into the western Gulf of Mexico and even then they would have to have the proper trajectory to impact us with extra rain, ala Hermine.

The GFS long range computer model projection for mid and late next week keeps hinting at tropical waves near the ITCZ (Inter Tropical Convergence Zone) at a lower latitude closer to South America.  If these come to pass, they would probably have a better shot at the mainland U.S. being less subjected to the “curvature” of passing systems in the middle latitudes. We’ll see!

It is always interesting to watch how a long range computer models pick up on hurricane possibilites over the Atlantic. One such model, called the GFS, will run out to 14 days!

In that time frame, “Igor” is seen cranking up and turning over the open Atlantic, avoiding the U.S. Today’s highlighted area in the southern Caribbean is not shown to develop much at all although you can trace its movement (small “L” on the map).
Tropical Depression #12 has formed behind Igor and it shows an almost parellel, more eastward track of Igor.

The further out in time this model projects, the less reliable it becomes. But it is interesting to note initialtion of another eastern Caribbean storm toward the end of the loop which develops into a named storm in the western Gulf of Mexico.

Yesterday’s model run showed TD #12 doing more of a stall or loop over the open Atlantic. Meanwhile, the Caribbean storm tracked more north and threatened Florida!

The next few tropical storm/hurricane names:

Rain Path of Erin 2007

Tropical Storm Hermine came ashore near south Texas last night and now the task of figuring out where the heavy rain arc will end up begins!

First off, the projected track looks a bit like that taken by the remnants of tropical storm Erin back in August of 2007.  That particular system activated rain over southwest Missouri and produced just shy of a foot of rain in Miller, MO (Lawrence County).

Hermine is projected to pass west of Springfield proper and this is where the heaviest rain is forecast to fall on Thursday.  The official Hydrological Prediction Center forecast of precipitation includes 3-4″ totals in an arc including western and central Missouri.

5 Day Rain Forecast

 Unforunately, the rain is projected into an area which has had plenty on average from late spring through the summer.  The dry areas in the Ozarks are along the Missouri/Arkansas border, especially the more east you head.

Visible Satellite Image of Earl 9/2/10 a.m.

There are three landfall possibilities for “Earl”, the outer banks of North Carolina, Cape Cod and Maine.

If Earl interacts with the approaching front and upper low in the right way, Maine may be the best shot at a U.S. landfall although as a much weaker tropical storm verging on extratropical low if it does.

Category four Earl has made a turn overnight and is moving more northward. It has strengthened to sustained winds of 145 mph.  This storm will affect the outer banks of North Carolina later tonight and hurricane warnings are in effect for this region.

As this storm continues north, it will encounter cooler ocean water and deeper wind shear, both of which tend to weaken hurricanes

The upper level winds should begin to grab Earl and send it northeast on Friday. This would exclude much of the east coast from the eye but of course the wind, rain and high surf will be a threat from the Carolina’s northward during Earl’s trek.

Powerful Hurricane Earl is on track to graze certain portions of the east coast. Cape Hatteras and Cape Cod both jut out east into the cone of potential travel for this hurricane.

I will be talking about Earl and discussing hurricanes in general at 1 pm today in my Atmospheric Science class at Missouri State University.  You can watch this LIVE on a special edition of  “Upstream” hosted by Ustream.  While I will not be able to chat during this lecture, with any luck it should record on the Ustream page along with other “Upstream” shows in case you are not able to watch live.

You can also track Earl on this website under the Tropics menu above.

Present thinking is that Earl’s eye will not officially make landfall.  It the impacts of heavy rain, wind, high surf and riptides will be felt from the Carolina’s northward to New England.

Earl is not forecast to become much stronger. It is encountering some wind shear which tends to break apart the circulation of tropical systems.

NHC Update Monday 8/30/2010

Danielle is weakening, Earl is up and coming and there might be a Fiona in our future!

Once category four hurricane Danielle is accelerating to the north and northeast now, far away from land. This storm will continue to weaken and lose its tropical storm characteristics and the jet stream grabs it and sends it over much cooler waters.

Meanwhile, Hurricane Earl is hitting Puerto Rico, the Virgin Islands and the northern Leeward Islands with heavy rain bands and squalls.  The storm is passing close enough to Puerto Rico for the eye to be seen on the National Weather Service radar located on the island.  You can get a link to this radar plus a great tracking map and more on the tropics page on this website.

There is of course some speculation on how close Earl will come to the mainland U.S.  Hurricanes are steered by the broad wind field they are embedded.  However, stronger storms actually help to modify the wind field and buck its tendencies a touch.  Also, there are still uncertainties as to what disturbances over the central U.S. will do.  My gut feeling on all of this?  A more westerly track but whether its enough to threaten the coast significantly remains to be seen.

Puerto Rico Radar from Monday AM

The North Carolina coast up to New England will be watching Earl carefully over the next four days for sure!Another wave is showing signs of development eastward from Earl and has a high probability of organization over the next few days.  The next name on the list is “Fiona”. Like Earl, this storm will take a more westerly and southerly track if it continues to develop and will likely be subjected to the same curvature only sooner meaning it would probably be less of a threat to the mainland U.S  But could give the northern Leeward Islands another hit.  Cooler waters in the wake of Earl might weaken this storm a tad.