Tropical Storm Karen

3 10 2013

We are under our first Hurricane Watch of 2013 from a threatening tropical storm named Karen.  TS Karen quickly intensified overnight due to favorable atmospheric conditions for strengthening.

One thing you will notice is the west side of the storm lacks any and almost all thunderstorm activity.  That is because of the storms counterclockwise rotation bringing in dry air into that region of the storm which will limit or even prohibit much thunderstorm activity.  The next following images are forecast tracks from various models.  The first will just be a track forecast while the next one will be a track and timing forecast.

Currently, the models hint at a landfall ranging from the mouth of the Mississippi River to Apalachicola, FL.  However, there is a focus from Waveland, MS to Pensacola, FL.  Depending on where it falls will make a dramatic difference because those to the west of the landfall location will not experience the full force of the storm.  This does not mean you will not see any strong winds or thunderstorm activity because the reason why TS Karen will curve like it does is because of a strong cold front sweeping across the U.S. and will begin to pick up TS Karen as it gets closer to the coast.  So, we will see a combination of tropical storm weather and thunderstorm activity from a cold front this weekend.

The intensity of TS Karen as it gets closer is still a bit uncertain, but vast agreement with tropical storm strength winds as it makes landfall.  If you notice on the previous image, most forecast models hint a landfall early Sunday morning which is just before 72 hours.  The graphic below shows forecast intensities by a number of forecast models.


Just by looking at this you can see that most models forecast it will make landfall as a tropical storm which is the light grey area.  Landfall timing is within the black oval which is between 60-72 hours ahead from the time this graphic was initialized.  Most agree with winds from 40-60 knots which is anywhere from 45-70 MPH.

TS Karen will have some issues it will face as it makes its trip to the Gulf Coast.  Graphics would be posted, but they are a bit confusing so I will just describe to you the issues.  One, and the biggest, issue is wind shear which is simply a change in wind and direction over a short distance in the atmosphere.  North and Northwest of TS Karen are strong upper-level winds that will shear the tops of the thunderstorms.  Those strong winds will limit the strengthening of the storm.  As TS Karen continues to move close to the Gulf Coast it will push the strong upper-level winds northward.  The problem with that is that if TS Karen makes a westward movement it will run into a slightly favorable environment until it gets close to land where part of it will be torn apart, due to strong winds, before making landfall which will weaken it.  If it keeps a more northerly track it will not get sheared as much from the winds and maintain some strong tropical storm strength until landfall.  Right now, either case is possible as tropical storms and hurricanes like to seek out the most favorable environment for them.  The curve will be due to a strong cold front moving across the U.S. which will be timed perfectly to pick up TS Karen.  The other issue is the dry air which will prohibit much rapid intensification throughout it’s lifespan.  Due to dry air and the wind shear it has a slight chance of becoming a weak category 1 hurricane for a brief time period, but will not maintain that status or get any stronger than that.

We will continue to heavily watch Tropical Storm Karen as a lot of football games and even a music festival, Bayfest, will be affected by it.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: