BIRDSEYE VIEW POSTS

Since 2012 on the Weather Underground (www.wunderground.com) blogs, I have been posting annotated "birdseye view" charts of the Atlantic basin, with a detailed explanation and forecasting that references the chart. From there you may know me as "NCHurricane2009." While I now do these "birdseye view" posts here, I will continue to do comments via Disqus on Weather Underground at www.wunderground.com/cat6. You can see my Disqus feed at this link for my latest comments. Feel free to reply to me with your disqus account or e-mail at IOHurricanes@outlook.com 

 
 
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MY 2021 ATLANTIC HURRICANE SEASON BIRDSEYE VIEW POST #44A (Special Update)

*******Note that forecasts and outlooks in this post are NOT the official forecast from the National Hurricane Center (NHC). They are my own detailed views on the Atlantic tropics based on current observations and latest computer model runs. As such do not make decisions based on my posts...consult news media...watches and warnings from your local weather office...and any evacuation orders issued by local governments to make the most informed and best decisions. Visit the NHC website hurricanes.gov (hurricanes dot gov) for the latest watches/warnings and official forecasts on active tropical cyclones.**********


…UPDATE…FRIDAY JULY 9 2021 2:28 PM EDT...

The NHC as of 2 PM EDT has declared Elsa a remnant non-tropical frontal cyclone. This does not change the fact that there will be impacts across the far northeastern US now and Nova Scotia and Newfoundland later today and tomorrow as the frontal cyclone remains vigorous (still packing 50 mph max sustained winds) while supported by upper-level divergence. These impacts will include gusty winds in the southeast half of the circulation…heavy rainfall…and coastal sea swells.


…UPDATE…FRIDAY JULY 9 2021 1:37 PM EDT...

Left: Satellite Image of Tropical Storm Elsa centered between the eastern tip of Long Island New York and Rhode Island…taken at 1456Z. Right: Doppler radar taken at the same time:

Tropical Storm Elsa has maintained enough thunderstorm activity…resultant latent heat release…and thus warm core upper outflow overnight to delay the transition to a cold core non-tropical frontal cyclone as it moves rapidly across the coastal northeastern United States. The center of the tropical storm is now seen making landfall across Rhode Island and eastern Massachusetts after it earlier skirted over eastern Long Island New York…and maximum sustained winds remain at 50 mph. As part of the circulation is over land and the other part is over cool water…the thunderstorm activity is instead supported by non-tropical means…specifically the divergence zone of the incoming upper trough to the west. The thunderstorm activity near the center as of late is fading and a cold front thunderstorm band extending south and offshore of North Carolina indicates Elsa is almost done transitioning to a non-tropical frontal cyclone. The area of heavy rains and flash flooding potential currently covers a region spanning eastern Connecticut to eastern Maine. Even though the storm track is slightly further west and closer to Maine…the strongest winds are still expected to miss Maine as Elsa is moving fast to the northeast such that the wind on the northwest side tends to be suppressed and wind on the southeast side tends to be enhanced. However coastal sea swells will include Maine if they have not started already. After the center departs Massachusetts…the heavy rains..,gusty winds…and coastal sea swells will move across Nova Scotia and Newfoundland later today and into early tomorrow.


Here are some of the strongest National weather service station reports of wind (in mph) generated by Elsa over the last several hours:

**Richmond VA…sustained 21…gust 29 (9:54 PM EDT July 8)

**Annapolis MD…sustained 12…gust 23 (12:54 AM EDT)

**Dover DE…sustained 14…gust 26 (12:56 AM EDT)

**Atlantic City NJ…sustained 23…gust 35 (5:54 AM EDT)

**Philadelphia PA…sustained 17 (6:54 AM EDT)

**Trenton NJ…sustained 14…gust 21 (6:53 AM EDT)

**New York NY…sustained 7…gust 21 (7:51 AM EDT)

**Hampton Bays NY (east end of Long Island)…sustained 23…gust 31 (now)

**Hartford CT…sustained 13…gust 24 (9:53 AM EDT)

**Providence RI…sustained 21…gust 30 (9:51 AM EDT)

**Barnstable MA (Cape Cod area)…sustained 21…gust 41 (now)

**Boston MA…sustained 21 (11:54 AM EDT)

**Worcester MA…sustained 17…gust 25 (now)

**Concord NH…sustained 6 (now)

**Portsmouth NH…sustained 14 (now)

**Portland ME…sustained 7 (11:51 AM EDT)

**Augusta ME…sustained 3 (now)


…THURSDAY JULY 8 2021 9:52 PM EDT...

Left: Satellite Image of Tropical Storm Elsa centered over southeastern Virginia taken at 0051Z. Right: Doppler radar taken at the same time:

Tropical Storm Elsa continues to gradually re-strengthen while aided by the divergent nature of upper flow on the east side of an incoming upper trough…and as of 5 PM EDT was estimated to now have 50 mph max sustained winds based on National Ocean Service (NOS) buoy data near Wrightsville Beach North Carolina. The quick-moving center of circulation has advanced into southeast Virginia and will already be zipping across the coastal northeast United States through tomorrow morning. The area of heavy rains and flash flooding potential currently covers a region spanning southeast Virginia to southern New Jersey…I recommend preparations for gusty winds from coastal New Jersey to coastal Massachusetts should have been completed by now…as well as preparation for coastal sea swells from coastal New Jersey to Maine. Preparations for similar impact south of New Jersey should have been completed long ago as the storm is now upon that area. Atlantic Canada (Nova Scotia and Newfoundland) is expected to be impacted by Elsa late tomorrow and Saturday after it completes transition to a non-tropical but still vigorous frontal cyclone.


Here are some of the strongest National weather service station reports of wind (in mph) generated by Elsa over the last few hours. Where surface friction is higher…inland areas are generally seeing less wind (check the list below from Fayetteville and down. Fayetteville and Greenville were exceptions as an inland wind event appeared to occur in the region around 5 PM EDT):

**Wilmington NC…sustained 23…gust 40 (1:53 PM EDT)

**Morehead City NC…sustained 23…gust 44 (7:58 PM EDT)

**Hatteras NC…sustained 26…gust 41 (now)

**Corolla NC…sustained 23…gust 35 (6:55 PM EDT)

**Elizabeth City NC…sustained 22…gust 37 (now)

**Norfolk VA…sustained 17…gust 37 (7:59 PM EDT)

**Salisbury MD…sustained 17…gust 24 (12:54 PM EDT)

**Dover DE…sustained 18 (3:56 PM EDT)

**Fayetteville NC…sustained 18…gust 37 (4:53 PM EDT)

**Greenville NC…sustained 23…gust 38 (5:15 PM EDT)

**Rocky Mount NC…sustained 16…gust 30 (6:53 PM EDT)

**Raleigh NC…sustained 15…gust 25 (11:51 AM EDT)

**Richmond VA…sustained 17…gust 23 (now)

**Annapolis MD…sustained 14…gust 26 (3:54 PM EDT)


For more on Elsa…it’s expected impact across the northeastern US and Atlantic Canada…and a check on the rest of the Atlantic tropics…see birdseye view post #44 on the home page of this site…also available at this link.

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