2005 Personal Tropical Seasonal Outlook

[DoctorHurricane2003]

S2K Disclaimer: The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

Personal Disclaimer: In addition, an official seasonal forecast issued by NOAA is located at the NHC website at http://www.nhc.noaa.gov/



I. GENERAL INTRODUCTION

This season is looking to be similar to last year. It should be an active season for the Atlantic, and a below normal season for the Eastern Pacific, similar to the majority of the past 9 seasons. This update is significantly changed from my December Outlook, and the June 1 and August 1 Forecasts are the only ones that are included in the statiscal results.

II. ATLANTIC BASIN

A. INTRODUCTION

The Atlantic Basin this season is looking like it will be similar to last year in most respects, as well as 2003 in others. In the following seasonal variables that affect seasonal numbers and storm tracks, an effect description will be given to the cause of POSITIVE, NEUTRAL, or NEGATIVE in its effects. For our purposes, POSITIVE is defined as an effect that helps to increase the numbers.

B. SEASONAL VARIABLES

1. EL NIÑO-SOUTHERN OSCILLATION (ENSO)

For this season, it appears that ENSO will be in a neutral state. An earlier Kelvin wave which briefly increased the chances of seeing a weak El Niño seems to have had no lingering effects. A cool tongue of water continues to linger in ENSO Regions 1-2, while ENSO Regions 3-4 seem to remain normal.

EFFECT DESCRIPTION: POSITIVE

2. QUASI-BIENNIAL OSCILLATION (QBO)

I still like to use QBO as a measure for intense hurricane formation, and it seems as if this played some part last year (QBO was Westerly, and we saw double the average number of major hurricanes). This year, QBO is expected to be easterly, so in effect, I am looking for a near normal amount of major hurricanes. However, it is IMPORTANT to note that QBO can change rapidly without warning as it did in 2003 from a westerly to an easterly direction. If QBO changes to a westerly description during the course of the season, major hurricane chances will increase.

EFFECT DESCRIPTION: NEUTRAL

3. SEA-SURFACE TEMPERATURE ANOMALIES (SSTAs)

Atlantic SSTAs are exceptionally above average, approaching near record numbers for this time of year, across the tropical atlantic. However, just off the coast of the Carolinas, they are slightly below normal. I expect that these SSTs will increase to a near normal level. For the tropical Atlantic, I expect that this will lead to a larger number of named systems in this region as well as a larger number of intense systems.

EFFECT DESCRIPTION: POSITIVE

4. NORTH ATLANTIC OSCILLATION (NAO)

The NAO is in a negative state, which corresponds to blocking patterns in the central Atlantic which easily leads to long-tracked systems as well as warmer sea surface temperatures.

EFFECT DESCRIPTION: POSITIVE

5. ARCTIC OSCILLATION (AO)

The AO also is in a negative state, and is similar to the NAO in that it corresponds to blocking patterns and warmer sea surface temperatures.

EFFECT DESCRIPTION: POSITIVE

6. ATLANTIC THERMOHALINE CIRCULATION (ATHC)

The ATHC is still in an active state, as it has been since 1995. This will correspond to a more active season.

EFFECT DESCRIPTION: POSITIVE

7. BERMUDA HIGH

The Bermuda High is starting to move into a similar position as last year. The majority of systems should have long tracks.

EFFECT DESCRIPTION: NEUTRAL/POSITIVE

8. MADDEN-JULIAN OSCILLATION (MJO)

I have removed the MJO from seasonal forecasts. Instead, it will be used as a general forecast in a month-by-month basis in selected comments.

C. ANALOG YEARS

For comparison purposes, the top three analog years to 2005, in chronological order, are:

1995
2003
2004

D. NUMBERS

With the seasonal variables as outlined above, I issue my forecast for the 2005 Atlantic Hurricane Season:

17 Tropical Depressions
16 Named Storms
10 Hurricanes
05 Major Hurricanes
Chance of Seeing a Category 5: 51%

I will note that with the Hurricane and Major Hurricane numbers, I am borderline between 9-10 Hurricanes and 04-05 Major Hurricanes, but since SSTAs are so high, I leaned toward the high side.

E. LANDFALL PROBABILITIES

This is my second year of completing landfall probabilities for locations on the coast. It was quite accurate last year, with the exception of the Texas coast.

In this section, I will give the percent chance of 100 that a tropical storm, hurricane, or major hurricane will strike somewhere in that zone this year.

80% - 100% Extremely Probable
60% - 79% Probable
40% - 59% Possible
20% - 39% Somewhat Possible
0% - 19% Unlikely

Zone 1: Brownsville, TX to TX/LA Border (Sabine Pass).
Zone 2: TX/LA Border (Sabine Pass) to LA/MS Border (Pearl River).
Zone 3: LA/MS Border (Pearl River) to Suwannee River, FL.
Zone 4: Suwannee River, FL to Cape Sable, FL.
Zone 5: Key West, FL to Key Largo, FL.
Zone 6: Homestead, FL to St. Augustine, FL.
Zone 7: Jacksonville, FL to Savannah, GA.
Zone 8: Savannah, GA to Cape Hatteras, NC.
Zone 9: Cape Hatteras, NC to Rehobeth Beach, DE.
Zone 10: Rehobeth Beach, DE to Newark, NJ.
Zone 11: Newark, NJ to Cape Cod, MA.
Zone 12: Cape Cod, MA to Eastport, ME.

TROPICAL STORM PERCENTAGES
1: 78%
2: 85%
3: 91%
4: 82%
5: 69%
6: 94%
7: 37%
8: 92%
9: 44%
10: 29%
11: 46%
12: 11%

HURRICANE PERCENTAGES
1: 51%
2: 60%
3: 71%
4: 65%
5: 39%
6: 79%
7: 20%
8: 77%
9: 33%
10: 21%
11: 25%
12: 04%

MAJOR HURRICANE PERCENTAGES
1: 30%
2: 47%
3: 49%
4: 44%
5: 16%
6: 52%
7: 13%
8: 43%
9: 20%
10: 10%
11: 12%
12: 02%


III. EASTERN PACIFIC BASIN

A. INTRODUCTION

This year, I am looking towards a below normal season once again for the Eastern Pacific. The QBO listed in section IIB. has the same effect in the Eastern Pacific. The remainder, other than ENSO, have no effect. What is listed in the following section are the changed effects of ENSO.

B. SEASONAL VARIABLES

1. EL NIÑO-SOUTHERN OSCILLATION (ENSO)

The Changed Effect is: NEGATIVE

C. NUMBERS

With the seasonal variables as outlined above, I issue my forecast for the 2005 Eastern Pacific Hurricane Season:

15 Tropical Depressions
13 Named Storms
06 Hurricanes
03 Major Hurricanes
Chance of Seeing a Category 5: 36%

IV. STATISTICS AND CONCLUSION

A. STATISTICS FROM PAST SEASONS

The following are statistics comparing my previous years' forecasts with the actual result:

Statistics Since 2001:

1.ATLANTIC
Actual/Averaged Forecast
2001:
Tropical Depressions: 17/18 (1)
Named Storms: 15/15 (0)
Hurricanes: 09/08 (1)
Major Hurricanes: 04/04 (0)

2002:
Tropical Depressions: 14/16 (2)
Named Storms: 12/15 (3)
Hurricanes: 04/07 (3)
Major Hurricanes: 02/04 (2)

2003:
Tropical Depressions: 21/19 (2)
Named Storms: 16/15 (1)
Hurricanes: 07/09 (2)
Major Hurricanes: 03/04 (1)

2004:
Tropical Depressions: 16/18 (2)
Named Storms: 15/15 (0)
Hurricanes: 09/08 (1)
Major Hurricanes: 06/04 (2)

AVERAGE NUMBERS:
Tropical Depressions: +/- 1.75
Named Storms: +/- 1.00
Hurricanes: +/- 1.75
Major Hurricanes: +/- 1.25

Standards: I take the absolute value of the missed number of depressions, storms, hurricane, and major hurricanes, and average each category.

2. EASTERN PACIFIC

Eastern Pacific Averages will begin with 2004. I do not recall any averages from 2001-2003, so I will save these averages for future use.

2004:
Tropical Depressions: 16/17 (1)
Named Storms: 12/14 (2)
Hurricanes: 06/07 (1)
Major Hurricanes: 03/03 (0)

AVERAGE NUMBERS:
Tropical Depressions: +/- 1.00
Named Storms: +/- 2.00
Hurricanes: +/- 1.00
Major Hurricanes: +/- 0.00

B. CONCLUSION

It looks like we will be in for a rough season in the Atlantic, once again. While statiscally, we should not see as many major hurricane landfalls as we did last year, I would not be surprised to see at least 2 major hurricanes make landfall. The Eastern Pacific should once again be slower than normal. For references, an updated seasonal forecast will be issued on or near August 1, 2005, after which no others will be issued unless exceptional conditions warrant.

***END***

[JTD]

Excellent, DoctorHurricane That post answered about a dozen questions I had about the season.

Well done!!

[Matt-hurricanewatcher]

Your hurricane knowlege blow me away. What a wonderful forecast discussion Doc hurricane.

[Scorpion]

Very informative and scary at the same time.

[cycloneye]

Well done doc.

[Brent]

Very good forecast... but SCARY.

[DoctorHurricane2003]

Thanks all.

Yes it is very scary. I am very glad that I will be moving to C PA this year! (I do NOT want to pick up a million shreds of shingles again!....and don't remind me of Agnes...) lol.......at least, assuming we don't get hit before August 20. :\

[senorpepr]

You and I are thinking along the same idea -- it's gonna be a rough season. I updated my forecast numbers yesterday and they happened to be very close to your numbers. Although my numbers didn't really account for too much science, it's mainly a slightly higher than normal based on the past decade's activity (minus 1997).

Anyway, outstanding discussion.

[cyclonaut]

Its good to be posting here along side the next Franks,Grays, & Bastardis.

J/K on the last one but its good to know that some of you guys & gals reallyknow your stuff out here!

Having said that...Man is it going to be a busy season!

[MGC]

How did you arrive at a 51% chance of a Cat 5? Good forecast though. I hope your numbers are wrong as with all the forecast of a super active season.....MGC

[DoctorHurricane2003]

Thanks again

I always get questions regarding the category 5 percentage. It's just a probability percentage...where the description is the same as under section IIE. percentages...the description for 51% being possible. But this is much above average. I arrive at it this time mainly because of the record SSTAs.

As comparison, last year's category 5 percentages were:

June 1: 39%
August 1: 41%

[StormChasr]

Your regions do NOT correspond to the TPC landfall possiblility zones. The same zone does not exist from Homestead to St. Augustine---the chances of seeing a hurricane in Dade county are 5 times greater than seeing one in St. John's county.

[DoctorHurricane2003]

Thank you, I know. But I'm not going to make a forecast for each individual coastal county....it takes too much time. Instead, and most logical, I just say "the east coast of FL," since the bermuda high steers things that direction. Its way too difficult to tell where exactly on the East Coast.....Miami versus Fort Pierce.....one will land this early. That is why I chose St. Augustine as a breakpoint.