2020 Hurricane Season (Atlantic & East Pacific)

Gaoth Laidir

The 2020 hurricane season officially starts on June 1st and runs until November 30th. This year NOAA is forecasting it to be an active season, with a 60% chance of above average, 30% of near average and 10% chance of below average. Their forecast confidence is 70%.

In numbers, they forecast 13-19 named storms (climate average is 12), of which 6-10 become hurricanes (climatic average 6), 3-6 of theses major (Cat 3 or higher) (climatic average 3).

Factors affective hurricane activity include nuetral ENSO or a possible La Niña, which in general reduces windshear, warm tropical Atlantic waters and an active African monsoon, which should supply plenty of easterly waves that could develop into tropical systems.

https://www.noaa.gov/media-release/busy-atlantic-hurricane-season-predicted-for-2020

We already had two weak and short-lived tropical storms in the latter part of May (Arthur and Bertha) and there is currently an area of interest in the mid-Atlantic, however this is not forecast to develop into a tropical storm.

List of 2020 Atlantic names:

Arthur | Bertha | Cristobal | Dolly | Edouard | Fay | Gonzalo | Hanna | Isaias | Josephine | Kyle | Laura | Marco | Nana | Omar | Paulette | Rene | Sally | Teddy | Vicky | Wilfred.

Latest SST anomaly



Useful links

http://www.nhc.noaa.gov/
http://hurricanes.ral.ucar.edu/realtime/current/
https://www.tropicaltidbits.com/
http://rammb.cira.colostate.edu/products/tc_realtime/index.asp
https://www.nrlmry.navy.mil/TC.html
http://tropic.ssec.wisc.edu/tropic.php
http://tropical.atmos.colostate.edu/Realtime/

Gaoth Laidir

In the eastern Pacific, Tropical Storm Amanda is a weak affair just making landfall along the Guatemala/San Salvador border. Heavy rain is the main threat.

sdanseo

With 19 predicted you'd imagine 22 is an outside possibility. Mother nature has done some very strange things in the last few years.

What happens if they run out of names? There are only 21 in the list.

Rikand

sdanseo wrote: »

With 19 predicted you'd imagine 22 is an outside possibility. Mother nature has done some very strange things in the last few years.

What happens if they run out of names? There are only 21 in the list.

https://en.m.wikipedia.org/wiki/2005_Atlantic_hurricane_season

The 2005 hurricane season ran out of names and started using Greek alphabet letters for the remaining storms. I'd imagine it's the same again if needed

Gaoth Laidir

The remains of ex-Tropical Storm Amanda from the eastern Pacific will probably develop into a new system in the Bay of Campeche in the next few days.

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. A large area of disturbed weather, associated with the remnants of
eastern Pacific Tropical Storm Amanda, is located over the Yucatan
peninsula of Mexico. This disturbance is forecast to move
northwestward over the southeastern portion of the Bay of Campeche
later today or tonight where environmental conditions are expected
to be conducive to support development, and a new tropical
depression is likely to form within within the next day or so. The
system is then forecast to drift west or west-southwest over the
southern Bay of Campeche through the middle of the week. Interests
along the coast of the Bay of Campeche should monitor the progress
of this disturbance. Regardless of tropical cyclone formation,
heavy rainfall is likely to continue over portions of southern
Mexico, Guatemala, El Salvador, Belize, and western Honduras during
the next few days. For additional information on the rainfall
threat, see products from your national meteorological service.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...80 percent.

Today marks the first day of the Atlantic hurricane season, which
will run until November 30. Long-term averages for the number of
named storms, hurricanes, and major hurricanes are 12, 6, and 3,
respectively.

The list of names for 2020 is as follows:

Name Pronunciation | Name Pronunciation

---

Arthur AR-thur | Laura LOOR-ruh
Bertha BUR-thuh | Marco MAR-koe
Cristobal krees-TOH-bahl | Nana NA-na
Dolly DAH-lee | Omar OH-mar
Edouard ed-DWARD | Paulette pawl-LET
Fay fay | Rene re-NAY
Gonzalo gohn-SAH-loh | Sally SAL-ee
Hanna HAN-uh | Teddy TEHD-ee
Isaias ees-ah-EE-ahs | Vicky VIH-kee
Josephine JOH-seh-feen | Wilfred WILL-fred
Kyle KY-ull

Two tropical storms, Arthur and Bertha, already formed this year in
May. The next named storm that develops this season will be
Cristobal.

Gaoth Laidir

That has now formed into Tropical Storm Cristobal. It is currently forecast to move northwards through the Gulf of Mexico towards the southern US states by the weekend, possible around 55 knots by then (but highly uncertain).

WTNT63 KNHC 021619
TCUAT3

Tropical Storm Cristobal Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL042014
1115 AM CDT Jun 02 2020

...DEPRESSION STRENGTHENS TO A TROPICAL STORM...

Observations from an Air Force Reserve Unit Hurricane Hunter
aircraft indicate that Tropical Depression Three has strengthened
into Tropical Storm Cristobal. The maximum winds are estimated to
be 40 mph (65 km/h) with higher gusts.

SUMMARY OF 1115 AM AST...1615 UTC...INFORMATION

---

LOCATION...19.3N 92.7W
ABOUT 150 MI...245 KM WSW OF CAMPECHE MEXICO
ABOUT 135 MI...215 KM NE OF COATZACOALCOS MEXICO
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...SW OR 230 DEGREES AT 3 MPH...6 KM/H
MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES

$$
Forecaster Pasch

Meteorite58

A new record, third named storm to form so early in the season. Looks like heading towards the Gulf coast at the weekend making landfall maybe Sunday or Monday, big uncertainty on track , timing and strength.

Rainfall the main issue at the moment across parts of Mexico and Central America.

Will be interesting to see how much it strengthens over water, some high SST's up near 29C

Gaoth Laidir

Still an awful lot of water to pass under the bridge in the next few days as Cristobal will first make landfall in eastern Mexico on Wednesday and then may or may not re-emerge over water again late Thursday/Friday.

Tropical Storm Cristobal Discussion Number 5
NWS National Hurricane Center Miami FL AL032020
400 PM CDT Tue Jun 02 2020

Observations from the Hurricane Hunters around midday indicated
winds to tropical storm force over the southwestern quadrant, so the
cyclone was named. Since that time, scatterometer data suggested
that the wind field has become a little more symmetrical. The
current intensity is held at 35 kt for this advisory, which is a
little above the subjective Dvorak estimates. Some strengthening
could occur overnight since the cyclone is in a conducive
atmospheric and oceanic environment. However, it now seems likely
that the system will make landfall over eastern Mexico on Wednesday
which should cause weakening. Assuming that the center emerges over
the Gulf of Mexico later in the week, some re-intensification is
forecast. However, stronger shear over the northern Gulf should
limit the increase in strength. The official intensity forecast is
close to the latest LGEM guidance.

Satellite and radar imagery from Mexico indicate that the cyclone
is moving slowly southward, or around 170/3 kt. The system appears
to be rotating within a larger cyclonic gyre centered over eastern
Mexico. The global models show that Cristobal will be trapped
between two high pressure areas and have little overall movement for
the next few days. However, the slow, cyclonically looping
movement of the cyclone should take the center over eastern Mexico
on Wednesday and Thursday. Later in the week, increasing southerly
flow should steer the system northward over the Gulf of Mexico and
near the northern Gulf coast by the weekend. The official track
forecast lies near the latest dynamical model consensus, and is
roughly in the middle of the track guidance suite. Given the spread
in this guidance, there is a significant amount of uncertainty in
the NHC forecast at days 4-5.

Key Messages:

1. Deadly flooding has already occurred in portions of Guatemala and
El Salvador, and Cristobal is expected to bring additional heavy
rainfall to portions of southern Mexico, Guatemala, Honduras, and El
Salvador, which could cause life-threatening flash flooding and
mudslides. Refer to products from your national meteorological
service for more information.

2. Tropical storm conditions will continue along the coast of
Mexico where a tropical storm warning is in effect.

3. Cristobal is forecast to begin moving northward across the Gulf
of Mexico on Friday, and there is a risk of storm surge, rainfall,
and wind impacts this weekend along portions of the U.S. Gulf Coast
from Texas to the Florida Panhandle. While it is too soon to
determine the exact location, timing, and magnitude of these
impacts, interests in these areas should monitor the progress of
Cristobal and ensure they have their hurricane plan in place.

FORECAST POSITIONS AND MAX WINDS

INIT 02/2100Z 19.1N 92.5W 35 KT 40 MPH
12H 03/0600Z 18.8N 92.6W 40 KT 45 MPH
24H 03/1800Z 18.4N 92.4W 35 KT 40 MPH...INLAND
36H 04/0600Z 18.2N 91.8W 30 KT 35 MPH...INLAND
48H 04/1800Z 18.5N 91.6W 30 KT 35 MPH...INLAND
60H 05/0600Z 19.1N 91.4W 35 KT 40 MPH...OVER WATER
72H 05/1800Z 20.4N 91.5W 40 KT 45 MPH...OVER WATER
96H 06/1800Z 23.7N 91.2W 45 KT 50 MPH...OVER WATER
120H 07/1800Z 28.0N 91.5W 55 KT 65 MPH...OVER WATER

Gaoth Laidir

Meteorite58 wrote: »

A new record, third named storm to form so early in the season. Looks like heading towards the Gulf coast at the weekend making landfall maybe Sunday or Monday, big uncertainty on track , timing and strength.

The active period of the past week has been driven by a strong pulse of the MJO passing from Phase 8 to 1 (eastern Pacific towards Africa). As it moves further towards the east towards phases 2 and 3 through the rest of June we should see a lull in activity.

Current MJO phase diagram.

Gaoth Laidir

Cristobal is now back out over the Gulf of Mexico after spending a couple of days over the Yucatan peninsula, where it weakened to a tropical depression. It doesn't have a typical tropical storm structure as dry air and moderate shear are affecting it. Its current intensity is 40 kt and it's moving northwards, expectwd to make landfall near New Orleans Sunday night local time. No major strengthening is expected before then, the main threat being heavy rainfall to its east and north.

Latest water vapour image.



Elsewhere, the Atlantic and Pacific are quiet, with strong shear and dry air covering most of the basins.

Gaoth Laidir

Cristobal is a bit of a mess as it approaches New Orleans with that dry air wrapped right around the centre. The NHC have admitted that it doesn't have a tropical storm structure and I reckon it will be reclassified as a sub-tropical storm later. Current intensity 45 kts and they don't expect any further strengthening before landfall later tonight. Radar is showing extensive rainbands, producing rain rates of 0.5-0.75 inches per hour along the eastern gulf states.

Latest water vapour

Gaoth Laidir

The disorganised sub-tropical depression located on the Gulf Stream off the east coast of the US has become a little better organised today and was named a Tropical Storm Dolly this afternoon. Current intensity 40 knots but it is moving northeastwards and over the colder side of the Gulf Stream boundary and will dissipate in 36-48 hours.

Gaoth Laidir

Tropical Storm Fay has formed and will affect the New York/New England area later today/tomorrow, mostly bringing a few inches of rain and some gale-force winds. Current max winds are 45 knots and not forecast to increase any further.

This system actually started off as a small disturbance in the northeastern Gulf last week and it crossed land from the Florida panhandle to the Atlanic off South Carolina. It slowly developed over the past two days as it passed over the Gulf Stream and in an area of weak shear.

https://www.nhc.noaa.gov/archive/2020/FAY.shtml?

Tropical Storm Fay Special Discussion Number 4
NWS National Hurricane Center Miami FL AL062020
800 AM EDT Fri Jul 10 2020

Surface observations and radar data from the KDOX WSR-88D radar
indicate that there is now an area of 34-kt winds extending north
and northwest of the center of Fay. These winds will be approaching
the coast of Delaware and the southern Delaware Bay in the next few
hours, and as a result the Tropical Storm Warning has been extended
southward to Fenwick Island, Delaware and the southern Delaware Bay.

No changes were made to the previous track or intensity forecasts,
however 34-kt wind radii were introduced in the northwest quadrant
at the initial time and at the 12-h forecast. No other changes
were made to the wind radii analyses or forecasts.

Note that this special advisory is being issued in lieu of the 800
AM EDT (1200 UTC) intermediate advisory.

Key Messages:

1. Fay is expected to produce 2 to 4 inches of rain with isolated
maxima of 7 inches along and near the track from the lower Maryland
Eastern Shore and Delaware northward into New Jersey, eastern
Pennsylvania, southeast New York, and southern New England. These
rains may result in flash flooding where the heaviest amounts occur.
Widespread river flooding is not expected at this time.

2. Tropical storm conditionsare expected along portions of the
mid-Atlantic and northeast coast today and tonight, and a
Tropical Storm Warning is in effect for the coasts of Delaware, New
Jersey, New York and Connecticut, including Long Island.

FORECAST POSITIONS AND MAX WINDS

INIT 10/1200Z 37.6N 74.7W 45 KT 50 MPH
12H 10/1800Z 38.9N 74.6W 45 KT 50 MPH
24H 11/0600Z 41.5N 73.8W 35 KT 40 MPH...INLAND
36H 11/1800Z 45.2N 72.7W 30 KT 35 MPH...INLAND
48H 12/0600Z 48.6N 70.9W 25 KT 30 MPH...POST-TROP/EXTRATROP
60H 12/1800Z 51.8N 68.8W 25 KT 30 MPH...POST-TROP/EXTRATROP
72H 13/0600Z...DISSIPATED

Latest visible satellite image.

Gaoth Laidir

Stucture-wise Fay is very asymmetrical and and main body of deep convection (red) has already affected coastal regions. Max rainfall so far is 5.25 inches in Virginia.

Gaoth Laidir

Fay is now a post-tropical depression after making landfall near Ocean City, NJ, last night. It didn't cause much of a fuss, with the highest gust recorded only 52 mph and highest sustained 39 mph. Rainfall totals were in the 2-4-inch range, with some isolated peaks above 5 inches.

star gazer

Tropical Storm Gonzalo has developed. One to watch, though it is a distance from anywhere right now. noaa
Something to be aware of is the complication that the pandemic could have if there are evacuations needed with social distancing making the sheltering of people more difficult. The fear of the pandemic and the fear of an incoming storm could come into conflict. Planning and messaging important.

Tropical Storm Gonzalo Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL072020
850 AM AST Wed Jul 22 2020

...TROPICAL DEPRESSION SEVEN BECOMES TROPICAL STORM GONZALO...

Satellite data indicate that Tropical Depression Seven has
strengthened and is now Tropical Storm Gonzalo with 45 mph
(75 km/h) winds. The intensity forecast will be updated in the
regular advisory at 11 AM AST...1500 UTC.

SUMMARY OF 850 AM AST...1250 UTC...INFORMATION

---

LOCATION...9.9N 43.1W
ABOUT 1250 MI...2010 KM E OF THE SOUTHERN WINDWARD ISLANDS
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES

There's also a potential system in the Gulf of Mexico.
Tropical storm Douglas could also cross over parts of Hawaii in the coming days.

Nabber

star gazer wrote: »

Tropical storm Douglas could also cross over parts of Hawaii in the coming days.

Looks likely to have lost its mojo on approach

star gazer

Duoglas has gone to a Major Hurricane and is forecast to become more of a threat to parts of Hawaii though still expected to lose much of its current strength by then.
TS Gonzalos looks like becoming a Hurricane shortly with a Hurricane watch in Barbados.
Tropical depression eight forecast to become a tropical storm and move over Texas at the lower level of storms but with heavy rains.

Oneiric 3

Thought this was interesting enough with this guy comparing the current season to that of 2005, but my God, do these American news people always have to shout at their audience? My advice is to watch with the volume low as his nasally accent/voice is particularly grating.

https://www.youtube.com/watch?v=KD4nGo-ys5A

star gazer

Hurricane Hanna developed out of the Gulf of Mexico depression moving towards the Texas coast bringing with it a lot of rain: 150mm - 300mm totals in South Texas into Mexico with isolated maximum totals of 450mm. The first Hurricane of the 2020 Atlantic Season.

TS Gonzalo weakened and is forecast to dissipate in the next two days.

Hurricane Douglas is on track to be at or near Hurricane strength as it reaches the Hawaiin islands. It's a Category two hurricane and expected to gradually weaken.

hatrickpatrick

I had a feeling this year would get off to a very active start and I wish I'd done a proper post about it back in May Last year had a weak Modoki form of El Nino wherein the Easternmost regions of the Pacific didn't warm up the way the Central Pacific did. This was similar to 2004, although a lot weaker. Much of the early hyperactivity of 2005 was attributed to a long period of convergence over the Central Pacific, which if you look back at SST charts was most likely caused by the Modoki pattern decaying and leaving the Nino regions cooling down much earlier in the season than it usually would if a La Nina pattern was going to develop.

The same happened this year to an extent, and the atmosphere responded with a La Nina-esque pattern of subsidence over the Pacific much earlier in the season than usual, which allowed wind shear to drop dramatically in the Caribbean and MDR. In fact, the only thing which prevented the kind of disastrous major hurricanes seen in July 2005 was a very southerly displacement of the African jet and ITCZ, which pushed tropical waves southwest into South America rather than allowing them to traverse the MDR and Caribbean. Had this not happened, even with the large Saharan dust plumes which dominated the Atlantic in early July, the SST and shear pattern across the tropical Atlantic would have provided rocket fuel for any tropical waves traversing the area.

Shear map from just a few weeks ago. Even in mid-September during the peak of hurricane season, it's exceptionally rare to see such low shear right across Caribbean like this. In July it's almost unheard of. As you can see, though, the tropical waves visible in the background are too far south to get any spin and avoid land interaction with South America.

I would therefore posit that the southerly displacement of tropical waves for the first fortnight of July was the only thing preventing a couple of extremely dangerous hurricanes from forming in the Caribbean.

Gaoth Laidir

Gonzalo has weakened to a remnant depression now instead of the hurricane it looked like being in previous forecasts. Lots of that SAL killed it.

Meanwhile Hurricane Hanna is making landfall along the south Texas coast.

Hurricane Hanna Tropical Cyclone Update
NWS National Hurricane Center Miami FL
AL082020 300 PM CDT Sat Jul 25 2020 ...
WESTERN EYEWALL OF HANNA BRINGING HURRICANE CONDITIONS TO THE COAST OF TEXAS...

A TCOON observing station at Laguna Madre, Texas, recently reported a sustained wind of 68 mph (109 km/h) and a gust to 104 mph (167 km/h).

NOAA buoy 42020 recently measured a gust to 87 mph (141 km/h) at a height of 12 ft (3.7 m) in the eastern eyewall of Hanna.

The most recent observations from an Air Force Reserve reconnaissance aircraft indicate that the minimum central pressure inside the eye of Hanna is 973 mb (28.73 inches).

SUMMARY OF 300 PM CDT...2000 UTC...

INFORMATION

---

LOCATION...26.8N 97.0W ABOUT 30 MI...50 KM ENE OF PORT MANSFIELD TEXAS ABOUT 75 MI...120 KM SSE OF CORPUS CHRISTI TEXAS

MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H

PRESENT MOVEMENT...W OR 260 DEGREES AT 8 MPH...13 KM/H

MINIMUM CENTRAL PRESSURE...973 MB...28.73 INCHES

star gazer

While not currently forecast to get to Hurricane strength, potential tropical cyclone nine (expected TS Isaias) is on track to impact a number of countries and potentially end up in Florida.

Gaoth Laidir

This thing is far from a tropical cyclone, though they have been issuing discussions on it as if it is. It's just an elongated trough without a closed circulation and max winds far off to its northwest. It seems everyone is chomping at the bit to get the ninth named system of the season but until it develops further the headlines will have to wait.

2020 has been record as far as the number of Atlantic named systems thus far goes, but these systems have all been tame affairs (even Hanna), and the season is below average with regard to hurricane days and major hurricanes.

In fact, the whole northern hemisphere is way below average so far. The northwest Pacific has remained pretty much dormant. Overall, the NH is running at about half the average activity.

http://tropical.atmos.colostate.edu/Realtime/

dfx-

Surely going over Dominican Republic/Haiti with its high terrain as a storm would do some severe damage to its strength

Gaoth Laidir

dfx- wrote: »

Surely going over Dominican Republic/Haiti with its high terrain as a storm would do some severe damage to its strength

Yes, and the NHC have refered to that in their latest discussion, slightly downgrading intensity at 48-72 hours. They have its max intensity at 50 knots in a couple of days.

star gazer

Tropical Storm Isaias has formed over night. It has some unpredictability with its large windfield to the North and how it might interact with the land in its path but heavy rains expected in several countries.

Tropical Storm Isaias Discussion Number 8
NWS National Hurricane Center Miami FL AL092020
500 AM AST Thu Jul 30 2020

Isaias is sending some mixed signals tonight. The 1-min rapid
scan data from GOES-16 indicates that the low-level center is likely
displaced west of a very intense burst of deep convection on the
northeastern side of the circulation. However, the satellite data
also shows increased banding features overnight and a more
organized central cloud pattern, with recent hints that perhaps a
low-level center is trying to re-form closer to the convection.
Radar observations from San Juan show 60-65 kt Doppler wind
velocities during the past few hours near 5000 ft, so the initial
wind speed is raised to 50 kt.

Model forecasts are showing a complex evolution of the tropical
cyclone during the next day or two. There is good agreement that
Isaias will move across Hispaniola later today, and its low-level
center will likely become disorganized over the high terrain.
However, the strong burst of convection currently near Puerto Rico
is associated with a mid-level circulation, which should pass
along the north coast of Hispaniola later today. Most of the model
guidance suggest that this feature will cause the re-development of
a surface center over the northern part of the broader system while
the mid-level circulation moves close to the southeastern Bahamas.
Afterward, the cyclone would then move northwestward until the
weekend, and gradually turn northward and northeastward close to the
U.S. East Coast into early next week ahead of a mid-latitude trough.
The official track forecast is a little to the east of the previous
one and close to the NOAA corrected dynamical model consensus. It
should be noted that further adjustments to the forecast tracks are
indeed possible, especially after Isaias moves north of Hispaniola.

The intensity forecast is quite tricky. In the short term, Isaias
is expected to move across Hispaniola, as the storm's interaction
with the mountainous island should cause some weakening and
disruption to the circulation. However, as mentioned before, the
models suggest that a new center could form, and the
environmental conditions would support gradual intensification.
The intensity models have been trending higher, and the official
forecast is nudged upward accordingly, now showing a peak
intensity of 60 kt when the storm is near the coast of Florida and
the Southeast U.S. Coast. It should be noted that there are models
that show hurricane strength near the U.S. but, given the large
amount of uncertainty, it is preferred to stay on the
conservative side for now. We should have a better idea of how
strong Isaias will become near the U.S. after reconnaissance
aircraft sample the storm and after it passes Hispaniola later
today.


Key Messages:

1. Isaias will produce heavy rains and potentially life-threatening
flash flooding and mudslides across the Virgin Islands, Puerto Rico,
the Dominican Republic, northern Haiti, and over the Bahamas.

2. Tropical storm conditions are likely across portions of the
the Virgin Islands, and Puerto Rico through this morning and will
spread westward to portions of the Dominican Republic, Haiti, and
the Turks and Caicos and the Bahamas later today and Friday.
Tropical Storm Warnings are in effect for these areas. Do not focus
on the details of the track forecast, as rainfall and wind hazards
will extend far from the center of the system.

3. While this system could bring some rainfall and wind impacts to
portions of Cuba and Florida later this week and this weekend, it
is too soon to determine the location or magnitude of those impacts.
Interests there should monitor the progress of this system and
updates to the forecast over the next couple of days.


FORECAST POSITIONS AND MAX WINDS

INIT 30/0900Z 17.2N 67.9W 50 KT 60 MPH
12H 30/1800Z 18.8N 70.2W 45 KT 50 MPH...INLAND
24H 31/0600Z 20.6N 72.9W 45 KT 50 MPH...OVER WATER
36H 31/1800Z 22.3N 75.5W 50 KT 60 MPH
48H 01/0600Z 24.0N 77.9W 55 KT 65 MPH
60H 01/1800Z 25.5N 79.2W 60 KT 70 MPH
72H 02/0600Z 27.3N 80.0W 60 KT 70 MPH
96H 03/0600Z 31.0N 80.0W 60 KT 70 MPH
120H 04/0600Z 37.0N 74.5W 60 KT 70 MPH

NHC Dixcussion 8

star gazer

Hurricane Isaias is due to strengthen further in the next day or so. A hurricane warning for the Bahamas is in place as it begins impacting its South Eastern islands. Current forecast track puts Isaias keeping just East of Florida without making landfall and going up the US East coast where landfall is a possiblity.

ABOUT 385 MI...620 KM SE OF NASSAU
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 305 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...990 MB...29.24 INCHES

NHC

Isaias: https://www.star.nesdis.noaa.gov/GOES/floater.php?stormid=AL092020#tab2

Oneiric 3

Well if the latest NOAA track is in anyway accurate, this will be a win for the GFS over the ECM, which must be a first.

Gaoth Laidir

Oneiric 3 wrote: »

Well if the latest NOAA track is in anyway accurate, this will be a win for the GFS over the ECM, which must be a first.

Not quite...

From the latest Discussion.

The 06Z UKMET and and GFS have shifted westward, closer to the Florida coast, which is similar to the westward shift seen in the 00Z ECMWF model fields.

sdanseo

TD TEN has gone from a blip, to 50% chance of cyclone, to a TD in less than 24hrs.

2 systems now and one more potentially in the Atlantic basin.

All Atlantic systems this year, though we are at I in the alphabet already, have been weak enough so far. Isaias a bit different, it exceeded the initial NHC speed predictions in very short order and even they are saying current wind speed estimate is probably conservative, but future forecast now seems downgraded a little again in the latest discussion (there were 80kt values previously)

Hurricane Isaias Discussion Number 15
NWS National Hurricane Center Miami FL AL092020
500 PM EDT Fri Jul 31 2020

Deep convection, with occasional overshooting cloud tops of -85C to
-90C just north of the center, has continued to develop during the
normal diurnal convective minimum period, which is quite impressive.
The most recent Air Force Reserve recon flight-level wind data,
along with ASCAT surface wind data, indicate that the inner-core and
outer wind field have both contracted in size. Furthermore, radar
data from the Bahamas and an 1810Z AMSR-2 microwave pass also
indicate that a small 10-nmi-wide mid-level eye is forming. The last
recon central pressure was 991 mb and the 700 mb height had
decreased by 30 meters since the earlier maximum height around
1230Z. These data indicate that Isaias is getting better organized.
The initial intensity remains 65 kt based on an earlier 700-mb
flight-level wind speed of 72 kt, which reduces to a 65-kt surface
wind speed using a 90-percent adjustment factor.

FORECAST POSITIONS AND MAX WINDS

INIT 31/2100Z 22.6N 75.7W 65 KT 75 MPH
12H 01/0600Z 23.9N 77.2W 70 KT 80 MPH
24H 01/1800Z 25.4N 78.8W 75 KT 85 MPH
36H 02/0600Z 26.8N 79.9W 70 KT 80 MPH
48H 02/1800Z 28.3N 80.4W 65 KT 75 MPH
60H 03/0600Z 30.0N 80.4W 60 KT 70 MPH
72H 03/1800Z 32.5N 79.4W 60 KT 70 MPH
96H 04/1800Z 39.0N 74.5W 55 KT 65 MPH
120H 05/1800Z 45.4N 65.9W 50 KT 60 MPH...POST-TROP/EXTRATRO