Post by hurricaner on Jan 13, 2016 15:21:31 GMT -6
SUBTROPICAL STORM ALEX ADVISORY NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012016 500 PM AST WED JAN 13 2016
...OUT OF SEASON SUBTROPICAL STORM FORMS OVER THE FAR EASTERN ATLANTIC...
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...27.1N 30.8W ABOUT 785 MI...1260 KM SSW OF THE AZORES MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...NE OR 55 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...990 MB...29.24 INCHES
SUBTROPICAL STORM ALEX DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012016 500 PM AST WED JAN 13 2016
Curved bands of cloudiness and showers/thunderstorms associated with the low pressure system over the eastern subtropical Atlantic have become better defined over the past 24 hours. Although the convection is not very deep, it is likely of at least moderate intensity given the relatively shallow tropospause over the area. Given the increased organization, and the apparent dissipation of nearby frontal features, advisories are being initiated at this time. The cyclone is co-located with an upper-level low, and appears to have only a weak warm core, so it is being designated as a subtropical storm. The current intensity is set to 45 kt in agreement with an earlier scatterometer overpass. A ship traversed the northern portion of the circulation earlier today and did not observe winds of tropical storm force and this is reflected in the advisory wind radii.
The cyclone has been turning toward the left as it moves in the flow on the east side of a shortwave trough, and the initial motion is northeastward or 055/12 kt. The trough is expected to continue to swing counterclockwise around a broader mid-latitude cyclonic gyre, and this should result in Alex turning northward and north-northwestward over the next several days. The official forecast track follows the dynamical model consensus.
Although the shear is not forecast to become very strong over the next several days, the cyclone will be moving over progressively colder waters. Therefore no increase in strength is shown for the next day or so. In the latter part of the forecast period, some strengthening is possible due to baroclinic processes. By 96 hours, the global models show the cyclone merging or becoming absorbed by another extratropical low at high latitudes.
Alex is expected to become an extratropical cyclone by the time it passes near or over the Azores, so no tropical storm warnings are being issued for those islands. However, gale force winds are likely to affect portions of the Azores beginning late on Thursday or early on Friday.
Alex is the first tropical or subtropical storm to form in January since an unnamed system did so in 1978, and is only the fourth known to form in this month in the historical record that begins in 1851.
Well we need to change the header for this thread we now have Hurricane Alex.
HURRICANE ALEX ADVISORY NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012016 1100 AM AST THU JAN 14 2016
...ALEX BECOMES A HURRICANE... ...HURRICANE WARNING ISSUED FOR THE AZORES...
SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...31.5N 28.4W ABOUT 490 MI...790 KM S OF FAIAL ISLAND IN THE CENTRAL AZORES MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H PRESENT MOVEMENT...NNE OR 20 DEGREES AT 20 MPH...31 KM/H MINIMUM CENTRAL PRESSURE...981 MB...28.97 INCHES
This is an interesting discussion on our new hurricane.
HURRICANE ALEX DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012016 1100 AM AST THU JAN 14 2016
Remarkably, Alex has undergone the transformation into a hurricane. A distinct eye is present, embedded within a fairly symmetric mass of deep convection. Water vapor imagery shows that the upper-level trough is now west of the cyclone, with divergent flow over the center - indicative of a tropical transition. It is very unusual to have a hurricane over waters that are near 20 deg C, but the upper-tropospheric temperatures are estimated to be around -60 deg C, which is significantly colder than the tropical mean. The resulting instability is likely the main factor contributing to the tropical transition and intensification of Alex. With these changes, the government of the Azores has issued warnings for most of the Azores islands.
The initial intensity is set to 75 kt in accordance with the analyzed Dvorak T-number of 4.5. Only slight additional intensification seems possible since the system will be passing over even colder waters during the next day or two. In 36 hours, the global models suggest that the cyclone will become extratropical as it begins to merge with a large low pressure area at high latitude. The post-tropical cyclone is then likely to lose its identity after 48 hours.
The initial motion is north-northeastward or 020/17 kt. Alex is being steered by a shortwave mid-level trough that is rotating around a larger trough to the northwest. This should cause the cyclone to turn northward and north-northwestward and accelerate over the next couple of days. The official track forecast is very similar to the previous one and also quite close to the consensus of the tightly-packed dynamical model forecast tracks.
Alex is the first hurricane to form in the month of January since 1938, and the first hurricane to occur in this month since Alice of 1955.
Post by DYLAN FEDERICO on Jan 14, 2016 10:12:42 GMT -6
What I want to know is how the hell did they know there was a hurricane in the middle of the Atlantic in January 1938? I feel as though a strong extra-tropical cyclone could easily be confused for a hurricane back then without satellite. I looked on the Internet and there isn't much.
Post by DYLAN FEDERICO on Jan 14, 2016 10:19:28 GMT -6
I finally found an explanation from HURDAT, on how they were able to realize there was a hurricane in the Atlantic in January 1938. It's pretty incredible how they were able to do it, and a great read.
Post by hurricaner on Jan 14, 2016 15:18:04 GMT -6
Latest on Alex.
HURRICANE ALEX ADVISORY NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012016 500 PM AST THU JAN 14 2016
...HURRICANE CONDITIONS EXPECTED OVER PORTIONS OF THE AZORES BY EARLY FRIDAY...
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...33.6N 27.8W ABOUT 350 MI...560 KM S OF FAIAL ISLAND IN THE CENTRAL AZORES MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H PRESENT MOVEMENT...NNE OR 15 DEGREES AT 23 MPH...37 KM/H MINIMUM CENTRAL PRESSURE...981 MB...28.97 INCHES