Montag, 23. Dezember 2013
Samstag, 30. November 2013
The end of the unusually quiet Atlantic hurricane season of 2013 is at hand.
The final tally of thirteen named storms was above the average of eleven for a season, but the two hurricanes (Ingrid and Humberto) and zero major hurricanes were well below the average from 1950 - 2012 of six and three, respectively.
The 2013 season ranked as the sixth-least-active Atlantic hurricane season since 1950, in terms of the collective strength and duration of named storms and hurricanes (ACE index), which was just 33% of the 1981 - 2012 average. The 2013 hurricane season was the first time since 1994 no major hurricanes formed, and was only the third below-normal season since the high-activity period for Atlantic hurricanes began in 1995.
NOAA and the U.S. Air Force Reserve flew 45 hurricane hunter aircraft reconnaissance missions over the Atlantic basin this season, totaling 435 hours--the fewest number of flight hours since at least 1966, said NOAA in a press release summarizing the 2013 hurricane season.
Dienstag, 22. Oktober 2013
The cloud pattern of Lorenzo has become better organized overnight and this morning. A burst of convection several hours ago has morphed into a central dense overcast with a band wrapping around the northern semicircle of the circulation.A series of microwave images have also shown a mid-level eye that is not coincident with the low-level center due to about 20 kt of westerly vertical wind shear. Unlike yesterday...however...the low-level center is underneath the convective cloud canopy. A blend of TAFB/SAB Dvorak intensity estimates and the latest ADT values is used to raise the initial intensity to 45 kt.Any further intensification of Lorenzo...if any...is likely to occur soon since the cyclone should encounter a substantial increase in northwesterly shear and move over gradually decreasing sea surface temperatures within 12 to 24 hours. The increase in shear should disrupt the vertical integrity of circulation and cause a decoupling of the cyclone in 24 to 36 hours.The system is likely become an open trough ahead of an advancing front by 72 hours. The NHC intensity forecast is raised in the very short term to account for the greater initial wind speed...but like the previous one...shows rapid weakening by 48 hours. Dissipation is now forecast a day sooner in agreement with the global model guidance.Lorenzo has been moving with more of an eastward component of motion...and the initial motion estimate is 075/07. The cyclone should be steered east-northwestward during the next day or two between a mid-level ridge to the south and a belt of westerlies to the north.The track should Bend more toward the northeast in about 48 hours as the steering flow becoming southwesterly ahead of a cold front. The NHC track forecast is slightly right of the previous advisory through 36 hours but not as far right as the multi-model consensus.Forecast positions and Max windsinit 22/1500z 29.5n 52.0w 45 kt 50 mph 12h 23/0000z 29.6n 50.8w 45 kt 50 mph 24h 23/1200z 29.8n 49.7w 40 kt 45 mph 36h 24/0000z 30.3n 48.7w 35 kt 40 mph 48h 24/1200z 31.3n 47.4w 30 kt 35 mph 72h 25/1200z...dissipated
Donnerstag, 3. Oktober 2013
An area of low pressure in the extreme southern Gulf of Mexico has been officially named as Tropical Storm Karen. It is located just north of the Yucatan Peninsula, moving north-northwestward. Maximum sustained winds have increased to 65 mph.
Karen will track northward across the central Gulf of Mexico the next 24 hours then move on a more northeasterly course later tomorrow through Saturday. Current model output takes the system into an area between Gulfport, Miss., and Panama City, Florida late Saturday night or Sunday morning.
The storm has undergone rapid intensification and this intensification process appears to be over. The storm is encountering moderate wind shear causing the upper level part to be tilted into the northeast. The stronger thunderstorms and wind are displaced to the east and northeast of the low level center. This tilted structure and continued shear will limit and perhaps prevent further intensification.
However, if the shear decreases for a few hours it might have an opportunity to reach hurricane strength. Recent satellite images show the low level center exposed well west of the stronger thunderstorms suggesting that won't happen anytime soon. As the system approaches the coast Saturday night, it will encounter even stronger shear causing the storm to weaken.
The main impact from Karen will be heavy rainfall along the central and eastern Gulf coast Saturday and Saturday night. Since this area has experienced above normal rainfall the past couple of months flooding might occur over some areas that don't normally experience flooding. Despite weakening Karen will bring rough surf along the west coast of Florida westward to the southeast Louisiana coast leading to a high risk of rip currents, coastal flooding and beach erosion. Tropical storm-force winds will arrive along the coast later Saturday, Saturday night into Sunday morning.
There is also the possibility of severe weather, including isolated tornadoes, as Karen makes landfall, especially east of the storm center. Once inland, it will spin down and become a big rainmaker for the southeast and eastern U.S. Sunday into early next week.
Jerry has weakened to a depression and will become a non-tropical sheared low pressure area within a few days as it moves over colder waters
Longer-range computer models show increased shear over much of the basin for next week. The Caribbean still appears to be an area that will have favorable development conditions due to very warm waters and low shear.
However, there will likely be several days before a tropical wave over the middle of the Atlantic currently reaches this area.
Dienstag, 1. Oktober 2013
Raus aus der Werft . . .
Schaden am Traktor . . . Schraube verloren . . .
weiter gehts . . .
vorsicht . . Kabel!!
da muss er hin . . .
und hinein ins Nass . . .
auf nach Bavaro.
Tropical Storm Jerry continues to slowly meander through the central Atlantic. It remains the only organized tropical system across the Atlantic Basin, but we continue to watch an area of disturbed weather in the Caribbean Sea for possible development.
Recent satellite imagery shows that Jerry is being impacted by wind shear from the north which is hampering further development. The center of circulation has also drifted southward over the last few hours. Steering flow will remain weak over the next 24 to 48 hours and Jerry will continue to slowly drift around the central Atlantic and not affect land. Toward the end of the week, we expect Jerry will turn more to the north and east as steering winds increase due to a storm system approaching from the west. We do not expect Jerry to become a threat to any land mass at least through this week.
A second area of interest is a cluster of showers and thunderstorms associated with a tropical wave situated across the western Caribbean. These showers and thunderstorms could become better organized as they drift northwestward and then northward into and through the northern Caribbean through midweek. An enhanced threat for heavier showers and thunderstorms will continue in Jamaica and central and western Cuba today as deeper tropical moisture moves through. We expect to see showers and thunderstorms with drenching downpours move into the Yucatan Peninsula by Wednesday.
After that, this will likely migrate into the central or eastern Gulf of Mexico. This feature will have to be watched closely as a depression or storm can form in this area while the wave tracks westward. The waters all across the western Caribbean are very warm, about 86 degrees F and are generally 83-86 degrees in the Gulf of Mexico, so there is plenty of fuel available for any tropical cyclone that might form in this area.
There are currently no other areas of concern in the Atlantic Basin.
Sonntag, 29. September 2013
Southwesterly wind shear over the depression is helping to displace some of the storms to the north and east; however, environmental conditions should be just favorable enough for some additional strengthening of this depression on Sunday. Thus, Tropical Depression 11 should become Tropical Storm Jerry sometime on Sunday afternoon or night.
As for the track, T.D. 11 will move slowly off to the east-northeast over the next day before ducking southward. Thereafter, the storm will briefly move toward the northwest, performing a loop, and ending up near its current position. By late week, T.D. 11 will be swept off to the north and east by a trough that is currently over the Midwest.
A second area of interest is a cluster of showers and thunderstorms situated across the central Caribbean. These showers and thunderstorms are gradually expected to become better organized next week as they drift northwestward into and through the northern Caribbean.
An enhanced threat for heavier showers and thunderstorms are likely across central and western Cuba next week as deeper tropical moisture moves across the country. By the end of next week, the feature of interest will likely migrate into the warm waters of the central or eastern Gulf of Mexico where further development into an organized tropical system is possible. This feature will have to be watched closely.
Mittwoch, 18. September 2013
Tropical Storm Humberto remains around 1,000 miles to the west-southwest of the Azores. Satellite imagery continues to show a fairly disorganized system with most of the thunderstorms to the east of the low-level center of circulation. This system will have a window over the next 24 hours or so to strengthen somewhat as shear lessens and it remains over ocean waters that are just warm enough to support tropical development as it moves off to the north.
Eventually, Humberto will be picked up by a cold front approaching from the west and very quickly accelerate off to the northeast by Friday and Friday night into cooler waters and it will transition to a non-tropical low pressure center by Saturday morning. We do not expect Humberto to impact any land masses over the next five days as it will remain well northwest of the Azores, making its closest pass to the islands Friday evening.
Aside from Humberto, we are watching an area of surface low pressure that is currently moving across the southern Yucatan Peninsula that is producing a large and disorganized swath of drenching showers and thunderstorms. An Air Force Hurricane Hunter Aircraft is scheduled to investigate this system later today if it becomes necessary to gather more information and data on it. This area of disturbed weather will move into the Bay of Campeche later today and then continue to slowly drift westward across the bay and into the southern Gulf of Mexico a few hundred miles to the southeast of Brownsville, Texas by Friday.
The low will be in an environment of low shear and warm waters, so we do expect it to become a tropical depression or even tropical storm over the next day or so. This system will then stall in the Gulf on Friday as an upper level system and cold front move into east and south Texas. If the upper level system extends far enough to the south it should draw this system north then northeast Friday night and Saturday. If this happens the system could move into the northern Gulf coast later Saturday or Saturday night as a tropical storm.
Another possible scenario is for the upper level system to bypass this developing tropical system. If this were to happen the system would be left to drift east then northeast slowly and then move towards Florida next week. Since there is a lot of uncertainty in the development and movement of this low pressure area we are urging all interests in and around the Gulf of Mexico to monitor the progress of this feature.
Elsewhere across the basin, no tropical development is expected in the next 24 to 48 hours.