Thoughts on 2013 Atlantic Hurricane Season

[ninel conde]

ryan maue

Ryan Maue ‏@RyanMaue 36m

Tropical wave to emerge Monday off Africa likely candidate for hurricane development. 10-15 days to add-up ACE.

[gatorcane]

Looking at the global models this morning it does seem like things will likely ramp up as expected in a week with the arrival of the MJO across the MDR in the Atlantic with all global models showing a tropical system forming east of the Leewards in about 7 days from now that some eventually develop into this year's first hurricane.

As Levi has stated in his last update, once we see one hurricane form out there, it could allow many to form in a relatively short period of time:

A pattern like this can accelerate activity rapidly. If the missing ingredient is added, we could quickly go from no storms at all to multiple storms simultaneously.

http://www.tropicaltidbits.com/

[ninel conde]

joe bastardi on a tweet storm this morning

Joe Bastardi ‏@BigJoeBastardi 43m

The current heightened period of hurricanes for the east coast has 5-7 more years to run, then its back to the 60s-80s as amo cools
Expand
Joe Bastardi ‏@BigJoeBastardi 44m

Very similar look to 1999 season which sent Dennis, Floyd and then Irene (1999) along east coast pic.twitter.com/2PKL8D04Di

several more im not posting as well.

[Gustywind]

Hurricane Season Update: No Hurricanes Through August? Is the Atlantic Hurricane Season Underwhelming?

Jon Erdman Published: Aug 23, 2013, 8:00 AM EDT weather.com

http://www.weather.com/news/weather-hur ... t-20130821


We're headed into the heart of the Atlantic hurricane season. August through October has accounted for 80 percent of the season's named storms from 1981-2010.

Through the first three weeks of August 2013, we've seen five named storms. Erin, the fifth named storm, became a tropical storm over two weeks ahead of the average E-storm pace (Aug. 31 is the average date, according to the National Hurricane Center).

The past three storms, however, Chantal, Dorian, and Erin, have all succumbed to dry air and/or wind shear before they could strengthen into hurricanes.

It's possible August could pass without the season's first Atlantic hurricane.

How unusual is this? Does that mean the rest of the season will be quiet?

Not Unusual

Aug. 10 is the average date the first Atlantic hurricane arrives, according to the National Hurricane Center.

Meteorologist Adam Dean (Twitter) and Dr. Matt Sitkowski, science and weather content coordinator (Twitter), both of The Weather Channel, found five hurricane seasons since 1960 in which the first hurricane did not form until September. They are listed below with the date of the first hurricane:
•2002: Sep. 11 (Gustav)
•2001: Sep. 8 (Erin)
•1988: Sep. 2 (Debby)
•1984: Sep. 10 (Diana)
•1967: Sep. 2 (Arlene)

Two of these seasons waited until the climatological peak, around Sept. 10, to produce the first Atlantic hurricane.

(MORE: Atlantic Hurricane Season Peak)

On average, this can happen every 10-11 years.

Not a Harbinger of a Quiet Season

Here's the total number of hurricanes in each of those five seasons lacking a hurricane through August:
•2002: 4
•2001: 9
•1988: 5
•1984: 5
•1967: 6

In the 30-year period from 1981-2010 the Atlantic Basin has averaged six hurricanes each season. As we've stated before many times, where the hurricanes track, not just numbers of hurricanes, is of ultimate importance for impact in any season.

As you can see in the slideshow at the bottom of this article, each of the five seasons featured at least one impactful, and in some cases intense, hurricane.

What was at the time the most intense Atlantic Basin hurricane on record, Hurricane Gilbert, occurred in the hurricane-tardy 1988 season.

Seven hurricane names were retired in those five late-start hurricane seasons. A committee of the World Meteorological Organization retires Atlantic hurricane names from future use when a storm is particularly deadly and/or destructive.

Hurricane Michelle in 2001 was the costliest tropical cyclone on record in Cuba (later topped by 2008's Hurricane Ike).

Still a Long Way to Go

The bottom line, here, is a late first hurricane has not historically correlated to an inactive Atlantic hurricane season.

We're headed into the peak of the hurricane season, the time during which vertical wind shear is at a minimum and instability, or the ability of the atmosphere to generate thunderstorms, is maximized.

An "average" Atlantic hurricane season (1981-2010) would still deliver the following after Aug. 31:
•7 more named storms
•4 hurricanes
•3 major hurricanes

Despite the inability of Chantal, Dorian and Erin to become hurricanes, all three managed to form in the deep tropics, well east of the Lesser Antilles. This is typically a sign of an active hurricane season.

Do you have a hurricane plan? Do you know if you live in an evacuation zone? Do you have adequate supplies for at least three days without electricity? Now is the time to prepare.

[ROCK]

JB is extremely biased when it comes to the EC and possible storm tracks. Not sure why that is.

[cycloneye]

Interesting articule about the first hurricane of 2013 season and what some experts discuss about this topic

[boca]

What I have noticed over the last two days is that convection is firing all over the Atlantic basin including the Caribbean which is a start.

[TropicalAnalystwx13]

Dr. Masters says,

Fernand's place in history
Fernand is the 6th consecutive named storm in the Atlantic that has not reached hurricane strength. Only one season since record keeping began in 1851 has had a longer string of consecutive storms that did not reach hurricane strength--2011, when the season began with seven such storms. However, it is quite possible such an event occurred before the advent of reliable satellite data in 1966, when we were first able to identify weak tropical storms that stayed out to sea. Several other seasons have had six consecutive tropical storms without a hurricane, most recently in 2002. The air over the Tropical Atlantic has been more stable and drier than usual (and was so in 2011), making it difficult for storms to attain hurricane strength.

An active weather pattern coming to the Tropical Atlantic
It's been an unusually quiet August for hurricane activity in the Atlantic, and if we finish the month without a hurricane, it will mark the first year since 2002 without an August hurricane. However, the quiet weather pattern we've been blessed with is about to come to an end, as conditions favorable for hurricane formation move into place for the last few days of August and the first week of September. The big guns of the African Monsoon are firing off a salvo of African tropical waves over the next two weeks that will find the most favorable conditions for development that we've seen this year. While there is currently a new outbreak of dry air and dust from the Saharan Air Layer (SAL) over the Eastern Atlantic, the latest European model forecast calls for a reduction in dry air and dust over the Tropical Atlantic during the 7 - 14 day period, accompanied by low wind shear. The Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, has begun a new active phase. The most active part of the MJO has not yet crossed into the Atlantic, but is expected to do so during the period 7 - 14 days from now. The MJO will bring rising air that will aid strong thunderstorm updrafts and thus tropical storms--and their subsequent intensification into hurricanes. According to Dr. Michael Ventrice, an MJO expert at WSI, Inc., the latest run of the GFS model predicts that this MJO event will be the 3rd strongest in the Western Hemisphere since 1989. During the last four comparable strong MJO events, 68% of all the tropical depressions that formed during these events (21 out of 31 storms) intensified into hurricanes. The MJO will likely continue to support Atlantic hurricane activity through September 15. The MJO is then expected to progress into the Western Pacific for the last half of September, which would likely bring sinking air over the Atlantic and a quieter portion of hurricane season.

http://www.wunderground.com/blog/JeffMa ... rynum=2501

[chaser1]

Dr. Masters says,

Fernand's place in history
Fernand is the 6th consecutive named storm in the Atlantic that has not reached hurricane strength. Only one season since record keeping began in 1851 has had a longer string of consecutive storms that did not reach hurricane strength--2011, when the season began with seven such storms. However, it is quite possible such an event occurred before the advent of reliable satellite data in 1966, when we were first able to identify weak tropical storms that stayed out to sea. Several other seasons have had six consecutive tropical storms without a hurricane, most recently in 2002. The air over the Tropical Atlantic has been more stable and drier than usual (and was so in 2011), making it difficult for storms to attain hurricane strength.

An active weather pattern coming to the Tropical Atlantic
It's been an unusually quiet August for hurricane activity in the Atlantic, and if we finish the month without a hurricane, it will mark the first year since 2002 without an August hurricane. However, the quiet weather pattern we've been blessed with is about to come to an end, as conditions favorable for hurricane formation move into place for the last few days of August and the first week of September. The big guns of the African Monsoon are firing off a salvo of African tropical waves over the next two weeks that will find the most favorable conditions for development that we've seen this year. While there is currently a new outbreak of dry air and dust from the Saharan Air Layer (SAL) over the Eastern Atlantic, the latest European model forecast calls for a reduction in dry air and dust over the Tropical Atlantic during the 7 - 14 day period, accompanied by low wind shear. The Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, has begun a new active phase. The most active part of the MJO has not yet crossed into the Atlantic, but is expected to do so during the period 7 - 14 days from now. The MJO will bring rising air that will aid strong thunderstorm updrafts and thus tropical storms--and their subsequent intensification into hurricanes. According to Dr. Michael Ventrice, an MJO expert at WSI, Inc., the latest run of the GFS model predicts that this MJO event will be the 3rd strongest in the Western Hemisphere since 1989. During the last four comparable strong MJO events, 68% of all the tropical depressions that formed during these events (21 out of 31 storms) intensified into hurricanes. The MJO will likely continue to support Atlantic hurricane activity through September 15. The MJO is then expected to progress into the Western Pacific for the last half of September, which would likely bring sinking air over the Atlantic and a quieter portion of hurricane season.

http://www.wunderground.com/blog/JeffMa ... rynum=2501

Well, short of Fernand being a "land-hugger", he certainly looked healthy and given another day or two over water, might easily had attained hurricane intensity. There is no doubt that the dryer sinking air over the MDR has had a significant impact on those tropical cyclones thus far; That coupled with less than favorable upper level conditions were thus far enough to inhibit further development and strengthening. Taking climatology into account as well as long range model tea leaves (as described by Dr. Masters above), it certainly would not be unreasonable for us to see approx. 5 more named storms with at least 3 becoming hurricanes, during the next 35 days. So, going on that presumption the bigger and more important question to me always seems to be the "where" rather than the "what".

If one looks at the present steering pattern, it would seem as if the long wave pattern has shifted (at least for now) and indicates a trough East of the Conus. Looking at the extended range (Euro & GFS), there "might" be the suggestion of ridging building back over the S.E. US in about 10 days, but is still too early to tell whether the deep Central U.S. trough at that time will come in phase with a westward retrograding long wave pattern or simply continue to progress eastward. This all said, and "assuming" the Atlantic purges its dry hacking cough.... my guess is that in terms of near term (4-12 days out) "risk factor"....., perhaps the Leewards, Virgin Islands, and possibly Puerto Rico might stand to have the greater risk of tropical cyclone impact. I think that Central America/Yucatan Peninsula also, but to a slightly lessor degree. Of course that is not to say that these areas will be "at risk", but given steering and weaker ridging in the W. Atlantic and present likelihood of near term re-curvature - I'd simply assume these area's would have a greater relative risk right now in comparison to the CONUS. I am also taking into account that conditions over the MDR are likely to become more conducive, thus lessening the chances of waves "squeaking" by and developing west of 60W. Now, if that were to occur and a fairly potent wave start to really convect in the East/Central Carib. with a potential weakness off the Eastern Seaboard...of course all bets would be off. Last night's 0Z GFS might have hinted towards something like that possibly happening in a 10-14 day range, but that feature was dropped on the 6Z run & will be interesting to see if it emerges again on the 12Z (and if developing & remaining at a more southern latitude).

[ninel conde]

Dr. Masters says,

Fernand's place in history
Fernand is the 6th consecutive named storm in the Atlantic that has not reached hurricane strength. Only one season since record keeping began in 1851 has had a longer string of consecutive storms that did not reach hurricane strength--2011, when the season began with seven such storms. However, it is quite possible such an event occurred before the advent of reliable satellite data in 1966, when we were first able to identify weak tropical storms that stayed out to sea. Several other seasons have had six consecutive tropical storms without a hurricane, most recently in 2002. The air over the Tropical Atlantic has been more stable and drier than usual (and was so in 2011), making it difficult for storms to attain hurricane strength.

An active weather pattern coming to the Tropical Atlantic
It's been an unusually quiet August for hurricane activity in the Atlantic, and if we finish the month without a hurricane, it will mark the first year since 2002 without an August hurricane. However, the quiet weather pattern we've been blessed with is about to come to an end, as conditions favorable for hurricane formation move into place for the last few days of August and the first week of September. The big guns of the African Monsoon are firing off a salvo of African tropical waves over the next two weeks that will find the most favorable conditions for development that we've seen this year. While there is currently a new outbreak of dry air and dust from the Saharan Air Layer (SAL) over the Eastern Atlantic, the latest European model forecast calls for a reduction in dry air and dust over the Tropical Atlantic during the 7 - 14 day period, accompanied by low wind shear. The Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, has begun a new active phase. The most active part of the MJO has not yet crossed into the Atlantic, but is expected to do so during the period 7 - 14 days from now. The MJO will bring rising air that will aid strong thunderstorm updrafts and thus tropical storms--and their subsequent intensification into hurricanes. According to Dr. Michael Ventrice, an MJO expert at WSI, Inc., the latest run of the GFS model predicts that this MJO event will be the 3rd strongest in the Western Hemisphere since 1989. During the last four comparable strong MJO events, 68% of all the tropical depressions that formed during these events (21 out of 31 storms) intensified into hurricanes. The MJO will likely continue to support Atlantic hurricane activity through September 15. The MJO is then expected to progress into the Western Pacific for the last half of September, which would likely bring sinking air over the Atlantic and a quieter portion of hurricane season.

http://www.wunderground.com/blog/JeffMa ... rynum=2501

today when the 12z gfs comes out we will almost be able to see out to the 15th of sept. if 3 or 4 storms havent formed by then the dry sinking air will have returned according to dr masters.

[ROCK]

today when the 12z gfs comes out we will almost be able to see out to the 15th of sept. if 3 or 4 storms havent formed by then the dry sinking air will have returned according to dr masters.

GFS over 7 days is la la land let alone 16 days. Not sure what your point is? we are still in August...

[tolakram]

12z 384 hour GFS It's September 11th, not the 15th.

[chaser1]

Dr. Masters says,

The air over the Tropical Atlantic has been more stable and drier than usual (and was so in 2011), making it difficult for storms to attain hurricane strength.

An active weather pattern coming to the Tropical Atlantic
It's been an unusually quiet August for hurricane activity in the Atlantic, and if we finish the month without a hurricane, it will mark the first year since 2002 without an August hurricane. However, the quiet weather pattern we've been blessed with is about to come to an end, as conditions favorable for hurricane formation move into place for the last few days of August and the first week of September. The big guns of the African Monsoon are firing off a salvo of African tropical waves over the next two weeks that will find the most favorable conditions for development that we've seen this year. While there is currently a new outbreak of dry air and dust from the Saharan Air Layer (SAL) over the Eastern Atlantic, the latest European model forecast calls for a reduction in dry air and dust over the Tropical Atlantic during the 7 - 14 day period, accompanied by low wind shear. The Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, has begun a new active phase. The most active part of the MJO has not yet crossed into the Atlantic, but is expected to do so during the period 7 - 14 days from now. The MJO will bring rising air that will aid strong thunderstorm updrafts and thus tropical storms--and their subsequent intensification into hurricanes. According to Dr. Michael Ventrice, an MJO expert at WSI, Inc., the latest run of the GFS model predicts that this MJO event will be the 3rd strongest in the Western Hemisphere since 1989. During the last four comparable strong MJO events, 68% of all the tropical depressions that formed during these events (21 out of 31 storms) intensified into hurricanes. The MJO will likely continue to support Atlantic hurricane activity through September 15. The MJO is then expected to progress into the Western Pacific for the last half of September, which would likely bring sinking air over the Atlantic and a quieter portion of hurricane season.

today when the 12z gfs comes out we will almost be able to see out to the 15th of sept. if 3 or 4 storms havent formed by then the dry sinking air will have returned according to dr masters.

I don't necessarily agree that the 2nd half of Sept. will be slow or inactive, even if the Atlantic were to only see 2 or 3 additional storms during the next 20 days. The reason I say that is right now there is greater suggestive climatology PLUS the potential enhancement of the MJO for the first half of Sept. Oddly, the 12Z run of GFS shows a 1010mb low just east of the Lesser Antilles at about 120hr. As I progress all the way out to 192 hours, the same darn low actually deepens very slightly to I think a 1007mb but during all this time barely moves and over 3 days has yet to develop and appears to have only progressed to a point roughly south of Puerto Rico.

My point is given all the "right" factors, there might still be enough really dry sinking air over the W. Atlantic basin, that significant development may continue to be inhibited (granted, these maps could change wildly and the next run or two could suddenly have the GFS biting on a deepening storm here). Having said all that, in spite of the fact that the MJO (and Elvis) "might have left the building" thus causing a general tendancy for less instability over the Atlantic at that time, may be far less relevent than all other factors (conditions) being generally favorable. It is my belief that a greater impact from the MJO might impact the tropics during June/July or perhaps Oct./Nov., but during the peak of the season, development is just going to occur baring significantly unfavorable conditions (low SST's, upper level wind shear, dry sinking air in the mid/upper levels, overall high sea surface pressures, etc).

So, I'd guess the dry air will eventually abate and the season will turn active....and more or less continue active. On the other hand, perhaps the dry air will stick around until October and we'll see 4-6 more T.S. struggle to survive. I think THIS "unknown" will ultimately be indicative of how the season plays out in terms of the season's big picture and could render the MJO as a contributing factor to a fairly active season or possibly relegate the MJO as a non-factor. Will be interesting to see how the next 2 weeks plays out, thats for sure.

[chaser1]

today when the 12z gfs comes out we will almost be able to see out to the 15th of sept. if 3 or 4 storms havent formed by then the dry sinking air will have returned according to dr masters.

GFS over 7 days is la la land let alone 16 days. Not sure what your point is? we are still in August...

Yep, for that matter....I'm sitting here looking at this potent system coming off the African coast at around 15N in about 90 hr.s, and am scratching my head that the GFS develops it and somehow keeps it around 40W & 20N at 192 hr.'s before finally whisking it away northward. Seems as if the pattern would yank that baby out of there a bit quicker than that with the mid Atlantic trough having decayed much of the ridging out there. If this wave were to not develop for days later, well then I'd guess there would be greater reason for it to progress westward. As it is, its already progged to come over water & develop 5 degrees farther north than other waves often might when they move off the coast & begin to deepen.

[gatorcane]

We are 15 days from the climatological peak of the Atlantic season of Sept. 10th.

If we don't see any hurricanes forming during this timeframe, I will definitely start to jump on the "this season is busting" bandwagon..

But still that is alot of time in the tropics and so much can change between now and then.

I would be shocked if we don't get at least one hurricane between now and then.

[chaser1]

We are 15 days from the climatological peak of the Atlantic season of Sept. 10th.

If we don't see any hurricanes forming during this timeframe, I will definitely start to jump on the "this season is busting" bandwagon..

But still that is alot of time in the tropics and so much can change between now and then.

Sounds like a great football score style "OVER/UNDER" (no wages ) bet!

1 Hurricane by Sept. 10 - OVER or UNDER???

Forever the optimist, i'll go with the "over"

[beoumont]

ITCZ looking healthy:

[gatorcane]

Yeah noticed that but look at all the dry air to the north

[Gustywind]

:uarrow: Yeah noticed that but look at all the dry air to the north

Hey Gatorcane, looks like one more week to hope that all that dry could move away...

[northjaxpro]

That is a lot of dry, sinking air out there right in the heart of the tropical Atlantic.

It is going to take awhile for the Atlantic to moisten up for sure.