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Spring 2014 Med/Long Range Discussion


andyhb

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Just had to make sure Andy saw this snippet of DVN's AFD from Feb. 5

MAJOR REGIME CHANGE STARTING DAYS 5 INTO DAY 10 NORMALLY SUGGESTMAJOR CHANGES IN SOLUTIONS AND PREDICTABILITY NEXT SEVERAL DAYS.THIS CHANGE WILL RESULT IN MUCH WETTER CONDITIONS ALONG WEST COASTWITH MILDER TEMPERATURES AT/BEYOND DAY 10 FOR CENTRAL US. THEMAGNITUDE OF ENERGY CHANGES IN THE PACIFIC ARE AMONG THE HIGHESTI HAVE SEEN OVER A 5 DAY PERIOD USING MULTIPLE SOURCES IN 35 YEARSOF ANALYSIS. THE MEANING...THIS WILL NOT BE A MINOR CHANGE ANDSHOULD RESULT IN MAJOR TEMP/MOISTURE CHANGES LASTING MANY WEEKSAND QUITE POSSIBLY MONTHS. TELECONNECTION WEIGHTING SUPPORTS MAYRESULT IN AN ACTIVE SPRING...MUCH MORE TYPICAL THAN WHAT HAPPENEDLAST YEAR WHICH THIS AUTHOR CORRECTLY ASSESSED WOULD HAPPEN LASTWINTER. THERE MAY BE SIGNIFICANT CHANGES IN KEY INDICES USED INTELECONNECTION TECHNIQUES NEXT SEVERAL WEEKS DUE TO THIS REGIMECHANGE. THIS WILL BE QUITE EDUCATIONAL TO MONITOR. THE REGIME WEARE ON A TRAJECTORY FOR...FAVORABLY SUPPORTS HIGHS IN THE 50S ANDPOSSIBLY 60S AT TIMES BY LATE IN THE MONTH...QUITE A CHANGE FROMPAST 2 MONTHS. THE WEST COAST AND INTER-MOUNTAIN REGION WILL SEEIMPRESSIVE RAIN TOTALS FOR AT LEAST THE NEXT FEW WEEKS. THIS MAYCONTINUE BASED ON ANALOGS AND STATISTICAL WEIGHTING INTELECONNECTIONS LOCALLY USED BY THIS AUTHOR...FOR MUCH OF THEEARLY TO MID SPRING...POSITIVE IMPACTS TO WESTERN DROUGHT...HIGHPW/S WOULD SUPPORT FLOODING RISKS THOUGH.
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Just had to make sure Andy saw this snippet of DVN's AFD from Feb. 5

MAJOR REGIME CHANGE STARTING DAYS 5 INTO DAY 10 NORMALLY SUGGESTMAJOR CHANGES IN SOLUTIONS AND PREDICTABILITY NEXT SEVERAL DAYS.THIS CHANGE WILL RESULT IN MUCH WETTER CONDITIONS ALONG WEST COASTWITH MILDER TEMPERATURES AT/BEYOND DAY 10 FOR CENTRAL US. THEMAGNITUDE OF ENERGY CHANGES IN THE PACIFIC ARE AMONG THE HIGHESTI HAVE SEEN OVER A 5 DAY PERIOD USING MULTIPLE SOURCES IN 35 YEARSOF ANALYSIS. THE MEANING...THIS WILL NOT BE A MINOR CHANGE ANDSHOULD RESULT IN MAJOR TEMP/MOISTURE CHANGES LASTING MANY WEEKSAND QUITE POSSIBLY MONTHS. TELECONNECTION WEIGHTING SUPPORTS MAYRESULT IN AN ACTIVE SPRING...MUCH MORE TYPICAL THAN WHAT HAPPENEDLAST YEAR WHICH THIS AUTHOR CORRECTLY ASSESSED WOULD HAPPEN LASTWINTER. THERE MAY BE SIGNIFICANT CHANGES IN KEY INDICES USED INTELECONNECTION TECHNIQUES NEXT SEVERAL WEEKS DUE TO THIS REGIMECHANGE. THIS WILL BE QUITE EDUCATIONAL TO MONITOR. THE REGIME WEARE ON A TRAJECTORY FOR...FAVORABLY SUPPORTS HIGHS IN THE 50S ANDPOSSIBLY 60S AT TIMES BY LATE IN THE MONTH...QUITE A CHANGE FROMPAST 2 MONTHS. THE WEST COAST AND INTER-MOUNTAIN REGION WILL SEEIMPRESSIVE RAIN TOTALS FOR AT LEAST THE NEXT FEW WEEKS. THIS MAYCONTINUE BASED ON ANALOGS AND STATISTICAL WEIGHTING INTELECONNECTIONS LOCALLY USED BY THIS AUTHOR...FOR MUCH OF THEEARLY TO MID SPRING...POSITIVE IMPACTS TO WESTERN DROUGHT...HIGHPW/S WOULD SUPPORT FLOODING RISKS THOUGH.

 

 

Would love to know what teleconnections they are looking at?

 

Not saying they are gonna be wrong.

 

Only big change i have seen is with the PNA. The EPO is as negative as ever ( despite modeling which said it would go positive for a lil while ) and the AO is at neutral. Typically this combo would favor more storms along the west coast ( this they are correct about )  and more of a se ridge BUT this is somewhat dependent on the Atlantic ( NAO etc ) etc. Does not support temps in the 50s/60s in the DVN area. If anything temps would be below normal out that way as the trough would be situated further west then what we have seen alot of this winter and thus from the GL to the west coast vs GL to east coast unless the NAO tanks then it is coast to coast below normal.

 

AGAIN not saying that is how it will all work out. Just explaining what usually happens.

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I know it's early and predictability is low but anyone have any early thoughts on spring severe season?  Preferably something that has some reasoning behind it.

 

Well one thing going for more action is the recent cooling in the enso regions. Almost have a Nina. This is very recent cooling though and thus could be a temporary thing. Would actually need a few more months to achieve a nina officially. Still something to watch for.

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February 2014 Thoughts...

 

Recent weeks have seen a rather dramatic cooling in ENSO Region 3.4. This is one signal of a cooler than normal February across the eastern half of the CONUS. Winters that preceded the development of an El Niño that had a January-March ENSO Region 3.4 anomaly of > 0°C typically featured a lot of warmth in February (1957 and 2002). Those that had an anomaly of < 0° often featured a lot of cool anomalies in February (1965 and 1968).

 

I noticed this post earlier in the winter mid/long range discussion thread on the main board, figured it could tie in here (and of course that 1965 shout-out would be rather intriguing for this board although it takes a lot more to get a ridiculous setup like you know what to happen  :P ), and with that I proceed to...

 

*Put on Don S. hat*

 

There isn't a strong ENSO signal currently (although there has been some recent cooling in the ENSO regions) so it will be difficult to use that to indicate any fluctuations in activity in a given region. Purely looking at historical analogs for ENSO alone, back to 1950, in years that started in January with a neg-neutral ENSO (0.0 to -0.5 generally) following at least 6 months of neutral-ENSO included all of 1960-1963 (relatively quiet years for the sub-forum region in particular, being more Plains-focused when there was activity), 1967 and 1968 (both featured some major events in the region including the 4/21/67 outbreak and the 5/15/68 outbreak in IA and adjacent areas), 1979 and 1981 (more Plains-focused again), 1982 (more active for the sub-forum including the Marion, IL tornado event), 1997 (MI folks might remember the 7/2/97 event in particular), 2002 (generally quiet everywhere aside from 4/27-28 until Fall) and last year (pretty sure I don't need to go over this one) so it is generally a mixed bag from this perspective. Some pretty impressive years are added if I also include pos-neutral ENSO in Jan from 0.0 to 0.5 such as 2004. There have also been some suggestions of an El Nino developing as we move further into the year although I'll save that for interpretation until later. Years that have seen a quick flip from a negative ENSO to a positive ENSO have been quite active on average, although generally a full-fledged La Nina has been active in these years prior to the flip.

 

Given the recent drought in the Desert SW, one could expect a bit of an enhancement to EML advection this Spring should such conditions continue.

 

It also may be worth looking into years with a very strong/persistent -EPO regime in January/moving into February, since this has been a dominant feature this past month.

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I noticed this post earlier in the winter mid/long range discussion thread on the main board, figured it could tie in here (and of course that 1965 shout-out would be rather intriguing for this board although it takes a lot more to get a ridiculous setup like you know what to happen  :P ), and with that I proceed to...

 

*Put on Don S. hat*

 

There isn't a strong ENSO signal currently (although there has been some recent cooling in the ENSO regions) so it will be difficult to use that to indicate any fluctuations in activity in a given region. Purely looking at historical analogs for ENSO alone, back to 1950, in years that started in January with a neg-neutral ENSO (0.0 to -0.5 generally) following at least 6 months of neutral-ENSO included all of 1960-1963 (relatively quiet years for the sub-forum region in particular, being more Plains-focused when there was activity), 1967 and 1968 (both featured some major events in the region including the 4/21/67 outbreak and the 5/15/68 outbreak in IA and adjacent areas), 1979 and 1981 (more Plains-focused again), 1982 (more active for the sub-forum including the Marion, IL tornado event), 1997 (MI folks might remember the 7/2/97 event in particular), 2002 (generally quiet everywhere aside from 4/27-28 until Fall) and last year (pretty sure I don't need to go over this one) so it is generally a mixed bag from this perspective. Some pretty impressive years are added if I also include pos-neutral ENSO in Jan from 0.0 to 0.5 such as 2004. There have also been some suggestions of an El Nino developing as we move further into the year although I'll save that for interpretation until later. Years that have seen a quick flip from a negative ENSO to a positive ENSO have been quite active on average, although generally a full-fledged La Nina has been active in these years prior to the flip.

 

Given the recent drought in the Desert SW, one could expect a bit of an enhancement to EML advection this Spring should such conditions continue.

 

It also may be worth looking into years with a very strong/persistent -EPO regime in January/moving into February, since this has been a dominant feature this past month.

 

 

Good disco..

 

Have at it.. EPO data back to 1948.:)

ftp://ftp.cdc.noaa.gov/Public/gbates/teleconn/epo.reanalysis.t10trunc.1948-present.txt

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Would love to know what teleconnections they are looking at?

 

Not saying they are gonna be wrong.

 

Only big change i have seen is with the PNA. The EPO is as negative as ever ( despite modeling which said it would go positive for a lil while ) and the AO is at neutral. Typically this combo would favor more storms along the west coast ( this they are correct about )  and more of a se ridge BUT this is somewhat dependent on the Atlantic ( NAO etc ) etc. Does not support temps in the 50s/60s in the DVN area. If anything temps would be below normal out that way as the trough would be situated further west then what we have seen alot of this winter and thus from the GL to the west coast vs GL to east coast unless the NAO tanks then it is coast to coast below normal.

 

AGAIN not saying that is how it will all work out. Just explaining what usually happens.

 

Looking at the EPO. The EURO and GFS have it going positive eventually. The WPO which has been negative for awhile looks to swing + again.

 

 

Maybe that meteorologist is looking at something else we're not. Maybe he doesn't believe the Greenland blocking will take root?

 

It would be interesting to hear more from him.

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  • 2 weeks later...

Was just looking at the latest drought maps and noticed the drought from here points west really hasn't improved since last summer.  We've had above normal snowfall here this winter, but very little rain.  Usually we get a few good soaking rains during a given winter, but really haven't had any this season.  Anyway, in the grand scheme of things the drought persists for the western MW.  What I'm wondering is if that could lead to another hot summer.  I'm not really into the seasonal forecasting thing, but I'm guessing if we don't get heavy spring/early summer rains from here on west we could be in for another hot summer. 

 

current_midwest_trd.png

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This might only interest Indiana folks but perhaps some of the same things can be found elsewhere.  It's a relatively new paper that looks at whether land use/land cover, ENSO phase, precip patterns, topography and other factors influence tornado occurrence and location.  Some interesting things in here.  Quick summary of some of the findings:

 

 

-Land use/land cover boundaries appear to play a role in touchdown frequency

 

-Topographical influences appear to play a role in parts of southern Indiana

 

-The rate of change of ENSO phase may be more important than the phase itself with increased tornado days in years with big swings

 

-Wetter years are not as favorable for seeing more tornado days

 

 

http://journals.ametsoc.org/doi/pdf/10.1175/2013EI000548.1

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This might only interest Indiana folks but perhaps some of the same things can be found elsewhere.  It's a relatively new paper that looks at whether land use/land cover, ENSO phase, precip patterns, topography and other factors influence tornado occurrence and location.  Some interesting things in here.  Quick summary of some of the findings:

 

 

-Land use/land cover boundaries appear to play a role in touchdown frequency

 

-Topographical influences appear to play a role in parts of southern Indiana

 

-The rate of change of ENSO phase may be more important than the phase itself with increased tornado days in years with big swings

 

-Wetter years are not as favorable for seeing more tornado days

 

 

http://journals.ametsoc.org/doi/pdf/10.1175/2013EI000548.1

Interesting read. Thanks for posting.

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Excellent discussion from Jeff Masters' blog by Mike Ventrice on the potential upcoming El Nino.

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2635

Definitely an excellent read. This wouldn't be a good development for anyone who wants an active severe weather spring, warm summer or active hurricane season in the Atlantic. If I'm not mistaken, spring 09 was very quiet in the severe wx department and spring '10 only picked up when the El Nino fully faded and the Pacific started to transition to a La Nina state.

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Definitely an excellent read. This wouldn't be a good development for anyone who wants an active severe weather spring, warm summer or active hurricane season in the Atlantic. If I'm not mistaken, spring 09 was very quiet in the severe wx department and spring '10 only picked up when the El Nino fully faded and the Pacific started to transition to a La Nina state.

 

Thing is, other years that have feature a rapid flip in ENSO towards an El Nino, even from a relatively weak neg-neutral signature have had some very significant events (see 1957, 1965 and 1982, which were all on the leading ends of strong Ninos). 09-10 by comparison was a later developing Nino than those.

 

Frankly I'd kind of welcome some sort of ENSO signal as a change from the stagnant activity we've seen the past 2+ years in the basin.

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Thing is, other years that have feature a rapid flip in ENSO towards an El Nino, even from a relatively weak neg-neutral signature have had some very significant events (see 1957, 1965 and 1982, which were all on the leading ends of strong Ninos). 09-10 by comparison was a later developing Nino than those.

 

Frankly I'd kind of welcome some sort of ENSO signal as a change from the stagnant activity we've seen the past 2+ years in the basin.

 

I am with you on this.. Historically speaking though there will be some weenies going off the deep end on this board if we get the typical Nino signal with temps during the summer while those like our famed cane chaser Josh leaves the country for good. Ofcourse he would probably get some decent action in the Pacific basin. Get a Nina then there is more of a fighting chance for the Atlantic basin, above normal temps and ofcourse severe action.

 

Personally i still think a few may be jumping the gun on the nino call especially those going with the mod/strong Nino. If we do get one to develop it probably wont be till the summer or later. We'll see anyways.

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For some reason the CFS decided to flip to mild for the entire last half of March. Tomorrow it flip flop back, who knows...

The trend to a +AO is interesting though.

Is there a 3/2 run of the weeklies not available at the link?

http://origin.cpc.ncep.noaa.gov/products/people/sweaver/cfs_fcst/

The 3/1 run of the weeklies is end to end colder than normal for the subforum.

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Well I take the snow maps with a grain of salt, but I figured the temperature maps are all going to be the same no matter what source.

 

The pay site i use look the same as CPC as well. Was mentioned in OT and one of the east coast sub forums about the temp maps also having issues. In this case though they were too cold.. Seriously.. I wouldn't trust anything put out by that outfit.

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