24 October 2013 Migration Report

Upper level southerly winds, though not strong, along with a dwindling season, yielded very light migration over the region last night.  Heaviest returns were in  the Puget Sound area and those were moderate at best.  San Diego is reporting their first Buffleheads, so you know it is pretty late in the season.

And with that — i’m headed into the field for the next three days and shutting down the blog for this season.  I will monitor the radar, as all radar junkies do, and if anything interesting pops up i’ll post it.  But barring that and conditions permitting, i’ll be back in the spring with the Turkey Vultures.

Here’s the radar loops from last night:

Base Reflectivity - Portland (KRTX)
Base Velocity - Portland (KRTX)
HCA - Portland (KTRX)

Base Reflectivity - Gray's Harbor (KLGX)
Base Velocity - Gray's Harbor (KLGX)
HCA - Gray's Harbor (KLGX)

Base Reflectivity - Seattle (KATX)
Base Velocity - Seattle (KATX)
HCA - Seattle (KATX)

And here is Paul’s archived National Composite

Here is the weather gallery:

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11 October 2013 Migration Report

Most of the action was to our north, while the Portland/Vancouver Basin only saw moderate levels of migration last night.  There were some pockets of heavy movement, just not widespread.  However, along the coast and across the Strait, birds were heavily on the move.  Maybe the localized rain dampened local spirits or they may just be happy to hang out for a while and enjoy our hospitality – we’ve got some really great bugs.

Whatever the case, it looks like some upper level instability will be moving into the area 24 to 48 hours out.  Which may disrupt things a bit, but i don’t see any rain and the winds should remain out of the north.  So we’ll see.

Tomorrow starts the weekend and i will be out in the field early.  So updates, if any, will be for archival purposes.

Here are last night’s radar soundings from the PNW radars (left click will take you to the loop):

Base Reflectivity - Portland (KRTX)
Base Velocity - Portland (KRTX)
HCA - Portland (KTRX)

Base Reflectivity - Gray's Harbor (KLGX)
Base Velocity - Gray's Harbor (KLGX)
HCA - Gray's Harbor (KLGX)

Base Reflectivity - Seattle (KATX)
Base Velocity - Seattle (KATX)
HCA - Seattle (KATX)

Here’s Paul’s National Composite

Here is the weather gallery (left click for larger image)

07 October Migration Report

I spent the weekend in the field, hence no weekend updates.

However, even with the great conditions migration levels were moderate with a few heavy pulses at best.  I put peak radar returns in today’s gallery.

It looks like we’re winding this season down.  Surely the neo-trops are long gone and we are now just waiting on the winter residents to complete the season.  I usually wait for the first Bufflehead to show up before i close the fall season.  But: another couple of days with a low trough draped over the region, only a hint of a ridge 48 hrs out, and modest returns over the weekend with ideal conditions — i’m closing this season early.  I will continue to review the radar and if anything noteworthy pops up i’ll put that up.

But barring that — that’s all folks!  Circumstances allowing, i’ll be back in the spring.  Hopefully with a fix for the lost animated radar loops.

KRTX Reflectivity loop
Regional loop.
Paul’s National loop.
Vorticity forecast

03 October 2013 Migration Report

A better flight than i expected last night.  Upper level winds were favorable and there was enough room between the storm cells for moderate levels of migration to take place.  To our north the migration was even heavy at times.  The Puget Sound was filled with birds as was the Washington coast.  Too bad it’s only Thursday as some of us have to work.  The next few days should be really great birding.

Here is the local KRTX Reflectivity loop.
Here is the local KRTX Velocity loop.
Here is the Regional Reflectivity Composite.
Here is Paul’s archived National Composite

The forecast remains the same with a really nice ridge of high pressure building in behind this last little bit of the plague of a low we’ve been dealing with.

Here’s the 72 hr. vorticity forecast
Here’s the 84 hr. winds aloft forecast.

A note on these links:  The regional level loops will break in a few days, NCAR does not archive the images past that.  Paul’s loop will remain in perpetuity — he’s like that.  The forecast links are dynamic and constantly updated.  That is; if you go to past posts and follow those links, they will look just like today’s link.  It sucks for archival information, but until i can recode my scripts it’s the best i can do for now.  I’ve poked around and it looks like Python might be another avenue.  I’ll see what i can do between seasons to hack around in yet another programming language.

Just a Reminder

Admin. Note:
I still haven’t resolved the technical issues around archiving the daily KRTX radar loops, and i may not be able to this season – we’ll see.

So, as a reminder, the local KRTX and Regional Composite loops that are linked to in the daily reports will only last a few day and then will be broken.  NCAR does not archive the radar images past a few days.  If you are visiting an older post and click on one of those and end up staring at a blank screen with a red “Preloading Images” icon — you’ll be waiting a LONG time – forever.  They’re gone.

However, Paul’s National Composite loops are archived on his site and these loops will display.

EOM – carry on.

PNW Migration Update – 21 May 2013

Strong westerly winds at elevation, pockets of rain and generally nasty conditions kept most migrants still headed north grounded last night.  There was a little pocket of birds taking off from the Gray’s Harbor area – probably stragglers of the shorebird and water fowl variety.  They didn’t get very far.  There were some moderate and widespread returns from California’s Central Valley so this isn’t over yet – but close.

The arctic low has moved south and is still dragging in a cold air mass, condensing moisture as it arrives – there’s even snow at higher elevations.  The center is up in BC so we’re getting the westerly winds at the bottom of the trough.  There is a high pressure ridge organizing out in the Pacific but it’s effects are a few days out.

Nationally the migration was heaviest in the northern fetches of the Mississippi Flyway.  The Atlantic Flyway was active in the Mid-Atlantic States.  For details refer to the regional NEXRAD trackers found in the sidebar links.  To take a look at the national migration picture click here where Paul Hurtado has archived last night’s event.

Admin Note:  This is the last update for this season.  I will probably do a final post in June where i’ll put up the intervening local radar loops for documentation.  Other than that — barring some meltdown — TTFN, be back in the fall.

Left click for larger gallery view:

PNW Migration Update – 19 May 2013

Winds with a mainly northerly component did not deter this last wave of migrants.  Except along the coast where the winds were up to 20 knots at altitude.  The migration pattern was again a signature of this season – moderate with patches of heavy returns.  The bulk of the birds were flying up the flanks of the Cascades.  We did see a very light but widespread flight come up out of the area around the mouth of the Columbia – captured in the Regional Composite.

A high pressure cell off the coast is dictating the conditions currently — clear skies and northerly winds.  There is a low squished between two highs that has some moisture associated with it, but it doesn’t look very strong and may only bring some cloud cover.  Notable is the high out in the Gulf of Alaska.  When the high pressure cells reach that latitude, summer is not far behind, but at this time of the year it can also pull down some cold arctic air.

Nationally the strong low that is wreaking havoc across the Plains States also pretty much shut down the Central Flyway. Some opportunistic migration between or behind squalls can be seen. The Mississippi Flyway was hopping however, especially up the Ohio Valley.  We are now seeing patterns that indicate this season’s migration is beginning to wain – not over, but definitely on the back side of the peak.  For details on migration back East check out the NEXRAD trackers in the side bar.  For a look at last night’s migration on a national level take a look at Paul Hurtado’s archived loop here.

Admin Note:  There will only be two more updates this season – i’m headed out on my annual trip to Malheur with the folks from the Audubon Society of Corvallis.  I may put up the archived loops without commentary once i get back from Malheur – depends on how they look.  But other than that — barring a meltdown in conditions — i’ll be back in the fall to watch the new crop of birds pick their way south.

Left click for larger gallery view:

Friday 21 September 2012

The weather has changed slightly as an upper level low pressure trough has pushed a  marine layer inland bringing cooler temperatures and a little precipitation.  The winds are light and variable with a bit of a southerly bias.

This will pose little challenge to determined southbound migrants but conditions are not optimal.  So last night we again saw only moderate amounts of birds moving through the area.  On the regional composite you can see sharply diminished returns along the coast and the Puget Sound again has the highest density of birds.  Through the night the bulk of the returns where along the western flanks of the Cascades.

I’ll be in the field again this weekend.  So, unless something inspiring happens this weekend to get me to post in the evening, the next update should be Monday the 24th.