CURRENT STATE OF THE TROPICAL ATLANTIC SYNOPSIS…MAR. 06, 2013…ISSUED 2:00 P.M. EST…PHFC

Good day all!

Going to do a little something different here today.  I wanted to go over a little bit of the state of the tropics.  Albeit some of the parameters or “signals” I look at for the upcoming hurricane season are not totally established, I do want to share what parameters I have, and should some of these continue toward negative, it would reinforce the premise of another above average hurricane season.

First, the current SST Anomaly map indicates continued slow cooling in the Equatorial EPAC.  Based on this , and current state of the atmospheric pattern, values suggest a still ongoing NEUTRAL ENSO pattern, albeit the SST anomalies have become a little cooler.  The map animation from Washington State University will how how this has progressed.

NOAA SST ANOMALY MAP

ANIMATED SST ANOMALIES


Looking at the SST Anomaly maps, there are a few things one can notice.

1.)  The Atlantic Ocean MDR is at or slightly above normal anomalies

2.)  The Atlantic Ocean Tripole is noted (warmer anomalies in the MDR, colder anomalies around 30N, and warmer anomalies north of that) becoming established.  This phenomenon allows for “lift” in the atmosphere in the Tropical Atlantic during the season, or what we cal net upward motion.

3.)  The presence of continued cooling in the Equatorial Eastern Pacific, which at the moment is producing ENSO NEUTRAL conditions.  Continued and sustained cooling could induce La Nina conditions for the season, albeit the Climate Models indicate Neutral conditions for this season.

4.)  The Gulf of Guinea has cooled somewhat, and is not as warm as earlier.  The significance of this is, with warmer anomalies, the ITCZ or Monsoon trof hangs out further south, with more rainfall over the Guinea region of Africa.  Cooler anomalies induce changes to where the ITCZ or Monsoon trof extends further north than average, bring rainfall to the western Sahel region.

WEEKLY AFRICAN RAINFALL

5.)  A Cold PDO is in place ( Horseshoe blue shape off the U.S. West Coast), which would have a tendency to quell any El Nino onset.

6.)  Indian Ocean anomalies have appeared to continue to cool slowly.  Cooler sst anomalies in the eastern portion of the Indian Ocean are indicative of a negative IOD, while the reverse is a positive.  During a negative IOD, the monsoonal circulation off of west Africa does not become interrupted, which allows for aid in more storm formation.  Based on the forecast of the IOD Index, a slightly negative IOD is forecast this upcoming season.

IOD FORECAST

7.)  The Southern Oscillation Index has recently showed a continued climb into the positive scale, which indicates Trade Winds blowing from east to west, which if remaining this way, would reinforce neutral conditions, if not a change to cool over time.

SOI

8.) The NAO has been negative, and is forecast to remain negative over the next week or two, which reduces trade winds in the Atlantic, thereby reducing wind shear, and allowing for the sst’s to warm.  Wind shear in the MDR, even though around 30 knots or so, is below climatology at this time.

NAO FORECAST

TROPICAL ATLANTIC WIND SHEAR

9.)  Although the QBO is no longer used as a forecast tool, USUALLY a positive phase leads to more hurricane development.  This feature could hit positive by the beginning of the season.

QBO (Bottom of chart)

So, pretty much in essence,  these factors are beginning to point to conditions favorable for another above average hurricane season, although these can change either way during the next 2-3 months.  Once we get into May, I’ll be looking at everything again to see where we stand.

Have a blessed day!

T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS 
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)
CoCoRaHS OBSERVER

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About palmharborforecastcenter

I am a Tropical Forecast meteorologist, providing hurricane forecasts during the Atlantic Hurricane Season. I retired from the U.S. Coast Guard in July of 2001. Meteorology became my passion in high school, and I have continued my educational background in meteorology since 1996, when I undertook the study of Tropical Meteorology. While working toward my degree, I had to unexpectedly withdraw from college due to my oldest sons medical reasons. I do however, meet the educational criteria of the AMS to be recognized as a meteorologist. Studies include, but are not limited to the Navy Aerographers Mate course, Naval METOC meteorology course, Meteorology 2010 Sophomore level course while attending St. Petersburg College, Clearwater, FL., Basic Forecasting course for operational meteorologists from Rapid WX, meteorology institute, a four month meteorological internship, and extensive research on numerous meteorological topics such as the MJO, NAO, satellite imagery interpretation, etc. I have been forecasting Tropical Weather (Tropical Storms and Hurricanes) since 1996, with my main client being three different Coast Guard Commands.
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6 Responses to CURRENT STATE OF THE TROPICAL ATLANTIC SYNOPSIS…MAR. 06, 2013…ISSUED 2:00 P.M. EST…PHFC

  1. Mike Doll says:

    Thanks Storm, We all ned to remember it only takes one hurricane to make it a busy year (landfalling) It is best to start your preperations early and check your supplies often!!!
    Mike

  2. Thanks Storm. I’m with LT…you’re over it as usual. I’ll pass this on to the Tropical gang. We’re still expecting a significant Winter Storm. However…it looks like most Models get it out of here faster. So…maybe not as much accumulation. Thanks again Storm and stay safe LT!!

    • originallt says:

      Hi Monty, yeah, I heard the Denver area could get up to 1 foot of snow with your next storm. So far here in SW CT. it has been a “BUST” No snow on the ground, winds are much less today, and the Baro. is around 30.00″ Coastal NJ did get hit pretty hard with winds and tidal flooding. Our winds are down to 10-20mph, WHG, from the N to NW. Let us know what you finally get. Thanks LT

      • Hery LT…yeah the GFS/ECMWF package is looking pretty good for a Major Winter Storm…I’m pulling for the other models!! Stay safe up there!! I’ll post significant snow accumulations as soon as I get them.

  3. originallt says:

    Thanks for this early Tropical out look. If anybody would have an idea of what is to occur this summer and fall, it would be you. Thank you Storm.– As for this coastal storm up here, it has proven very hard to forecast and get it right. So far only sprinkles and on and off light showers, windy, with Temp. around 40F Just now, the local mets have backed off from there snow forecast of earlier that said 4-8″, Now down to 2-4″ by Thursday night. Baro. is down to 29.88″ and not falling very fast. I think this baby is going more East than North East thus keeping the worst of it, out to sea. I’ll report in Later tonight. LT Stamford CT.

    • originallt says:

      Up-date it has just started to snow here in SW CT. Maybe by 7am on thurs. we’ll have an inch on the ground. Another round of snow is forecast for late Thurs. afternoon or evening, continuing into Friday morning. This batch of snow, expected to leave, 3-5″ of snow by Friday morning. Well, I’ll believe that when I see it. Still 37F now, winds NNE at 20-30mph with gusts to over 40mph. Barometer stuck at 29.93″–hasn’t moved in about 7 hours.

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