Tuesday, October 27, 2015

This extratropical cyclone





This large mess of moisture is going to try and consolidate into a single centre of low pressure as a fairly strong extratropical cyclone over the next 2 days.


Now(ish):



A mess!


Thursday(ish):


Gales of November!!!!!!! sub 990 low over superior!!!!
(note the precip no longer shows in Canada....) screw you WPC


So what does it mean for birding? Well I hope the mess of rain on Wednesday grounds waterbirds around the S. Great Lakes... Could be a good time for large numbers of mergansers, gulls and loons. The 850mb wind level on Wednesday looks CRAZY:


(~1.5km up)


BUT - the strong S winds (at 850mb) are fully overlayed by rain. This is why i think it has grounding potential (if anything is moving) but LITTLE southerly vagrant potential (some but not exceptional potential). After the system starts to wrap up, we get some strong SW winds on Lakes Erie and ON on Thursday:


Note the better structure of the low here


The winds originate from MB in this image - so not terribly far away, but at least in Franklin's Gull territory. Personally, I would be keen on whatever waterbirds are grounded on Wednesday - OR that are already present in the region (from earlier events) becoming concentrated by the strong winds at a popular birding spot (like Buffalo/Ft. Erie)... 

As far as CASW go - the heavy rains - and then cold SW winds - do not look promising to bring any more to our area, but presumably some are around from the recent zonal flow event. 


---


The phasing of the jet in a situation like this (with a strong low) is the standard "gales of november" where we get cold arctic air mixing with warm subtropical air/moisture in our region. The low originating from the gulf of Mexico is related to the long-since-dead remnants of Hurricane Patricia that hit the Pacific coast of Mexico several days ago. The most interesting element (to me) is the fact that the low hung around Texas/Louisiana for a few days (and was decently strong) before shooting north and hooking into our weather event. The fast-moving nature of the system would be promising for interesting birds - BUT - it is my thought that the very heavy rain would block any long-distance movements. Then we are left with the "back side' of the storm, which could be quite promising for central/western birds like Eared Grebe or Franklin's Gulls (or Pacific Loons, Western grebe etc)...

The added bonus of very strong winds (esp Thursday) could help us "find" anything that was already present before the storm arrived. 

Another thing I haven't mentioned is that all air flows into these lows, so there is no reason to think that some insane rarity won't be found (if you're out looking) - it's just that there may not be reason to expect anything MORE than the typical "Gale of November"!




And if you're like me - being quite fond of birding AND stormy weather (storm birding)- boom! 



1 comment:

  1. I'm with ya. A system this windy and rainy at this time of year...something cool with be blown in and/or knocked down. The question is, from where? Franklin's Gull is on my radar with this one. I am stuck working the weekend, unfortunately. Hopefully there will be some excitement with this one.

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