NIUmetGF

For the Anchorage area people tell me that this was a really good summer. I've only been here since mid-March. I think we've hit 70F (21C about) only a handful of times and not much over. Feels pretty good though.

ECMWF showing a significant low deepening into the Gulf early next week, GFS on-board but not nearly as strong

On a side note, the King Salmon NEXRAD PAKC has been out of service for quite a while and needs major repairs. Apparently now it is a funding issue and may not be fixed until next fiscal year.....

Had a visitor in Anchorage for a week, playing catchup here in the thread. That is some unusual lightning Patrick good catch. Great pictures MTBLANC keep it up. Your -35 picture reminded me of my Grand Forks, ND days. Coldest I felt was -38F. We certainly are entering a very active pattern here in southern Alaska. Wave after wave for the considerable future, with a couple of decent surface lows entering the Gulf. Already received .27 inches this morning.

Welcome to the board MTBLANC. Good to have another poster here, it's hard for Patrick and I to keep the discussion going all the time.

Hard to get a feel for the size of this system just looking at AK

While the Euro was off on the MSLP I think it progged 973mb it pretty much nailed the threat for the area 7 days out.

Saw this on a co-workers facebook, but it looks as if Alaska is the only place in the northern hemisphere experiencing any baroclinic pain. My link IR satellite

I was going to delve into vertically propagating mountain wave since one did develop later in the evening in this particular case but kept this post relatively short. You are right, no strong downslope winds developed, in fact the winds in Dillingham were even westerly off of Bristol bay in the afternoon and seemed almost decoupled from the flow aloft though this wasn't the case. I'll see if I can find a situation with our local wrf though I hear sometimes wrf can get alittle mountain wave happy.

Rather than make a long post here, I blogged about some local terrain effects. I struggled with going between technical/non-technical for non-met types so it's kind of in a grey area in between. http://mtlawsonwx.wordpress.com/2011/08/15/the-effects-of-terrain/

Is this C.C.?

http://www.nasa.gov/images/content/578373main_20110808_Merbok-AIRS_full.jpg In other news, the remains of Merbok are giving the models fits in the long range forecast

A moist southwest flow and compact potential vorticity anomaly is continuing a climatologically wet pattern to south central Alaska today. The dynamic tropopause (1.5 PVU surface) extends down to almost 550 mb with the stratospheric intrusion bringing some very dry air close to -80 C dew point. Doesn't look like much at first glance. Doing some QC on the incoming data I figured I had a faulty hygristor when I first saw the dew point tank. After looking at the upstream sounding from Bethel (PABE) from 00z and the recent 12Z it appears as if it is good data. Aug 9th 12Z for Anchorage (PAFC) and Bethel (PABE)

Looks like the GFS has backed off the -2 to -4 C 850 mb temps it was outputting yesterday. Not surprising considering the ridging/warm 850 T's (+12 C extending up into the Beaufort Sea) to the northeast cutting it off from any reinforcing cold air and a warm southwest flow behind the north Pacific ridge. Strange to think of a system being "cut-off" when it is on the polar side of the jet. This type of a pattern seems to favor climatology with a mean trough centered over western Alaska and the Bering Strait. You can see the July/Aug mean 500mb geopotential height pattern isn't too far off from what is happening now. climo current The major difference I see is the high latitude block over Greenland which has acted to shift the polar vortex toward the Chukchi/Beaufort Seas. This developing pattern is depicted well in the ensemble mean forecasts of several teleconnectors.... The progged positive PNA makes sense with the deepening low and embedded disturbances moving south into the Bering Sea will act to build the heights downstream over the intermountain west though I think the + phase is more related to the negative height anomalies over the Aleutians. The negative NAO at the same times shows the developing positive height anomolies over Greenland. All of these factors make for a cooler wetter period for southern Alaska. I am no teleconnector guru by any means, but just my take on the current pattern.

I see the GFS is progging the return of the 0 degree 850mb isotherm to southern Alaska. Nobody wants to see termination dust around here yet!

Does look like some decent instability, but not the "short/fat" (concentrated in the lower levels 0-3km) type CAPE more of the "narrow/skinny" cape reaching farther up in the atmosphere. As csnavy referred to, not much in the way of directional shear. You'd like to see the winds backed at the surface(at least past southerly) to increase the potential for streamwise vorticity. Another thing you'd like to see is more of an elevated mixed layer (warm/dry air overtop/capping the moist low levels)