Fiona | 130 mph and 932 mb peak | Extremely powerful Bomb Cyclone

[FortySixAnd32]

31 minutes ago, MaineJay said:

Just about captured

 

Pac Man meet Godzilla!!

[Burr]

Back up to 130mph winds in the last advisory

SUMMARY OF 1100 AM AST...1500 UTC...

INFORMATION

----------------------------------------------- LOCATION...35.9N 64.2W ABOUT 250 MI...405 KM N OF BERMUDA ABOUT 600 MI...970 KM S OF HALIFAX NOVA SCOTIA

MAXIMUM SUSTAINED WINDS...130 MPH...215 KM/H

PRESENT MOVEMENT...NE OR 45 DEGREES AT 35 MPH...56 KM/H

MINIMUM CENTRAL PRESSURE...936 MB... 27.64 INCHES

 

[Hiramite]

Am I allowed to post snow maps in the Tropical thread?   About 8" max.

[StretchCT]

 

[StretchCT]

Still sending a mission into Fiona.  From St. Croix. So far they've flown over 1,000 miles and they still have a couple hundred to go.  It's 700 miles or so to Cape Cod which has a base and 800 miles or so to Dover or the Joint base in NJ.  

[Iceresistance]

9 minutes ago, StretchCT said:

Still sending a mission into Fiona.  From St. Croix. So far they've flown over 1,000 miles and they still have a couple hundred to go.  It's 700 miles or so to Cape Cod which has a base and 800 miles or so to Dover or the Joint base in NJ.  

This is the last mission for Fiona, then all of the focus will be towards 9/Ian

[Sentinel]

23 hours ago, Burr said:

Help… For those of us who sit in the back of the classroom, some of the characteristics we’d expect to see during a transition from tropical (warm core) to hybrid / extra-tropical (cold core) include… 

~ expanding wind field

~ asymmetry of the vertical stack

~ acceleration of forward speed

… what else?

Sorry - I meant to answer this last night, however, you pretty much nailed it. 

BUTTTTTTT, let's go back to fundamentals right quick - and then we will move further. 

For barotropic (Heat Fueled) storms - Latent heat is the fuel. The heat turns the water into water vapor. As the water vapor rises (heat rises), it begins to condense. In order to condense, heat must be removed. When this heat is removed, it is known as latent heat, which in turn provides energy for the storm. 

For Baroclinic (gradient) based storms - Clashes of temperature allow for venting and instability, which allow for storm development. 

Now in regards to transitioning - You have a storm switching from a heat based storm to a gradient based storm. As such, you have declining SSTs and increasing shear. This shear is actually helpful for allowing Baroclinic storms vent and develop (Though sometimes it actually is helpful for Barotropic storms as well). 

So what do we see? 

First we see a significant expansion of the wind fields. In fact -many times- we will see the storm deepen while simultaneously seeing max wind speeds decrease. The reasoning for this is because the pressure is more evenly distributed and therefore the force is more evenly distributed. However, the total energy actually increases. This increase is important because lower winds can now lead to increased damage as these winds are buffeting a given point for a longer period of time. 

We also see precipitation expand to the NW of the system while decreasing to the S and W of the storm. This is due to the transition lending to the genesis of fronts; cold fronts to the South and Warm Fronts to the N/NE and backing NW. This warm front creates a focal point for precipitation with some of these fronts allowing for increasingly significant rainfall totals. 

Likewise, we see a net increase in speed. This net increase in speed can sometimes be significant enough too cause increased wind damage. For example -In 1938- the Long Island Express was moving so quickly that it actually increased wind speeds enough to allow parts of Long Island to experience wind speeds equivalent to that of a Cat 4 Hurricane, though it was officially designated a Cat 3 at Landfall (The category has been disputed over the last decade, however, this is for another time). 

Another thing to look for is significantly cooler air behind a storm. This creates 2 potential issues. 

1) Those who have lost power now have to deal with potentially frigid temperatures.

2) It lends the possibility of creating a secondary baroclinic zone with the potential for a strong mid latitude cyclone to affect the same areas within a 2-4 day time frame.

Other changes are on a more technical level and rarely impact the sensible weather observed. 

[StretchCT]

5 minutes ago, Uscg Ast said:

Sorry - I meant to answer this last night, however, you pretty much nailed it. 

BUTTTTTTT, let's go back to fundamentals right quick - and then we will move further. 

For barotropic (Heat Fueled) storms - Latent heat is the fuel. The heat turns the water into water vapor. As the water vapor rises (heat rises), it begins to condense. In order to condense, heat must be removed. When this heat is removed, it is known as latent heat, which in turn provides energy for the storm. 

For Baroclinic (gradient) based storms - Clashes of temperature allow for venting and instability, which allow for storm development. 

Now in regards to transitioning - You have a storm switching from a heat based storm to a gradient based storm. As such, you have declining SSTs and increasing shear. This shear is actually helpful for allowing Baroclinic storms vent and develop (Though sometimes it actually is helpful for Barotropic storms as well). 

So what do we see? 

First we see a significant expansion of the wind fields. In fact -many times- we will see the storm deepen while simultaneously seeing max wind speeds decrease. The reasoning for this is because the pressure is more evenly distributed and therefore the force is more evenly distributed. However, the total energy actually increases. This increase is important because lower winds can now lead to increased damage as these winds are buffeting a given point for a longer period of time. 

We also see precipitation expand to the NW of the system while decreasing to the S and W of the storm. This is due to the transition lending to the genesis of fronts; cold fronts to the South and Warm Fronts to the N/NE and backing NW. This warm front creates a focal point for precipitation with some of these fronts allowing for increasingly significant rainfall totals. 

Likewise, we see a net increase in speed. This net increase in speed can sometimes be significant enough too cause increased wind damage. For example -In 1938- the Long Island Express was moving so quickly that it actually increased wind speeds enough to allow parts of Long Island to experience wind speeds equivalent to that of a Cat 4 Hurricane, though it was officially designated a Cat 3 at Landfall (The category has been disputed over the last decade, however, this is for another time). 

Another thing to look for is significantly cooler air behind a storm. This creates 2 potential issues. 

1) Those who have lost power now have to deal with potentially frigid temperatures.

2) It lends the possibility of creating a secondary baroclinic zone with the potential for a strong mid latitude cyclone to affect the same areas within a 2-4 day time frame.

Other changes are on a more technical level and rarely impact the sensible weather observed. 

This is an excellent post. 

[StretchCT]

Goodnight 

[Burr]

[StretchCT]

 

[MaineJay]

Not sure I believe sable Island is only getting 46mph winds right now.

[MaineJay]

I could stare for hours at this. Almost has the scorpion's tail.

[StretchCT]

Vort messages showing mid 930s.

HDOBs way lower in the 926-927 range

Limited Sonde data, but still with flight level winds of 130mph.

So winds don't seem that bad.  Pressure wise, this would stand to be the strongest storm to hit Canada. 

Another way to look at it.

Edited September 24, 2022 by StretchCT

[StretchCT]

Recon flew over 1700 miles to get to the center. 

Left St Croix at 18:32, got to the center at 23:53. 

Last center fix was 150M SE of Fishermans Harbor

Edited September 24, 2022 by StretchCT

[StretchCT]

METARS from Atlantic Canada

https://en.allmetsat.com/metar-taf/maritime-provinces.php?icao=CWRN

Liscombe seeing 35/55mph

Halifax has gusts to 58mph.

[StretchCT]

Henry Island gusts up to 69mph

[StretchCT]

One more from the metars

[Chinook]

2 hours ago, StretchCT said:

Recon flew over 1700 miles to get to the center. 

Left St Croix at 18:32, got to the center at 23:53. 

Last center fix was 150M SE of Fishermans Harbor

Could you imagine a 3400 mile round trip, just to specifically find the highest turbulence in a noisy propeller plane? And then you have to look at your computer and analyze data while going through the highest turbulence.

[Chinook]

McNabs Island close to Halifax Harbor, peak wind 69 knots or 79mph, north-northwest

Quote

METAR: CXMI 240400Z AUTO 33049G65KT 11/10 RMK AO1 PK WND 34069/0317 T01050104

 

[TLChip]

Edited September 24, 2022 by TLChip

[Mainiac]

She's a chonky gal. Definitely feeling the winds this morning in north eastern Maine. 

[Chinook]

wind gust 72 knots, peak wind 79 knots

 

Edited September 24, 2022 by Chinook

[StretchCT]

931mb should be the new record low pressure for Canada.  https://www.theweathernetwork.com/ca/news/article/hurricane-fiona-makes-landfall-in-nova-scotia-historic-storm-far-from-over-prince-edward-island-newfoundland

[StretchCT]

https://twitter.com/EddieSheerr/status/1573679848375083008