About Blizzard92
Ph.D. Student - Earth System Science (UC Irvine), B.Sc. - Atmospheric Sciences (Cornell University)
First Rain of the Season for Southern California
By: Zachary Labe , 10:10 PM GMT on September 13, 2015
Zachary Labe
13 September 2015
http://sites.uci.edu/zlabe/blog/
A deepening trough will position itself across the western United States to start off the week. Remnants from Hurricane Linda will track eastward along the base of the trough and right entrance quadrant of the weak jet streak allowing for an ideal upslope flow of moisture into southern California. 
While a temporary drying of the midlevels is allowing cooler conditions and a drop in dew points over California this afternoon, increased moisture will begin advecting over the region this evening in addition to a lower strato-cumulus cloud deck. Temperatures for most of the week will be below normal, but overnight lows will be mild in response to warm SST's and increased boundary layer moisture.
Showers will begin moving into the Los Angeles basin and San Bernardino Mountains during the day Monday and gradually sink southward by nightfall. PWATs will begin to increase to 1-2SD above normal and a westerly flow off the warm Pacific will aid in additional orographic lifting for the coastal mountains. Heavy rain will be possible at times toward Monday night across the higher elevations, particularly toward the Big Bear region. Slightly elevated instability may allow for a rumble of thunder at times and rain rates in excess of 0.3"/hr in any convection that forms. Showers will sink southward slowly overnight Monday.
Less forcing and some dry air around H925 along the coastal valleys will preclude heavier rain totals with QPF generally at or below 0.4" for most locations. Even lesser rain totals can be expected near San Diego and on southward.
Global and mesoscale models have been steadily decreasing total QPF from this event over the last few runs, and therefore, maximum totals will likely stay around 1.0-1.25 inches. Nevertheless, given the moist sounding and upslope flow, most areas will receive some rain for areas west of the mountains in southern California.The most widespread rain is expected in Orange, western Riverside/San Bernardino, and southern Los Angeles counties.
Most of California remains in an "exceptional drought" according to the latest U.S. Drought Monitor. While this rainfall will barely put a dent in the seasonal rain deficits, it is falling at a time that is normally dry across southern California.
Average September Rainfall:
-Irvine : 0.2"
-Los Angeles : 0.2"
-Pasadena: 0.4"
-San Diego : 0.2"
The rain also falls on the heels of some last week courtesy of monsoon moisture and afternoon convection that even moved along the coast of Orange County. This is a good sign for the upcoming winter as strong El Ninos often produce an active atmospheric river/pineapple express flow bringing excess rainfall to southern California. Both the CFS and ECMWF weeklies suggest above average precipitation is expected for the late September/early October time frame. For now, after this week's rain we can expected some increasing upper level heights and a return to a mild and slightly above normal temperature pattern by next weekend over southern California.
Lower Susquehanna Valley Doppler...
(Courtesy of WGAL)
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My Personal Research and Blog Website: http://sites.uci.edu/zlabe/
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.
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67. jerseycityjoan
7:59 PM GMT on April 01, 2017Now he's in graduate school and the blogs are ending.
I am sorry that Wunderground no long wants us to spend much time on its site. Obviously the plan is to offer less and make Wunderground.com a quick check-in place, not a destination for lingering and socializing.
I want to extend my thanks and best wishes to Blizz and the gang that made his blog a daily destination for me for years.
Good-Bye and Best of Luck to all.
Joan
66. listenerVT
12:20 AM GMT on March 20, 2017As you may know, the WU blogger blogs are going away on April 3rd. :-(
If you'd like to be able to blog after that, we're moving over to a Facebook group that is deemed a "secret group" ~ meaning no one can see it except members of the group (so no trolls)! If interested, send me a message on WU Mail or to my email address jschulte at together.net and I'll add you to the group.
One has to have or make a Facebook account, but if that makes you uncomfortable you can simply use your blog name and only use Facebook for this purpose. Just one idea.
I hope everyone here considers coming over to the FB group, because it's so much fun during blizzards and learning together. Anyway, it's easy to post photos and graphics there! In fact, Pcroton and Sully are letting us post their Twitter graphics and notes over there, so it's the best of both worlds. I hope to hear from Blizz. P doesn't do Facebook but Sully says he'll come over sometimes, so that will be awesome.
Fare thee well! Hoping to see you all pop up in my Inbox yet! :-) listenerVT
63. weathernewbie
7:38 PM GMT on February 08, 2017Storm brewing here, but really miss checking in here to "See what Blizz says."
Will forward the link to your paper to a friend at the Princeton Institute for International and Regional Studies in the Global Systemic Risk group. They've been researching catastrophic agriculture failure. There's a team at Columbia University researching the topic as well.
Have you ever visited the Princeton Plasma Physics Lab? Wonder how you think it stacks up (in the weather department) to other similar facilities in the country.
Hope things continue to go well- and you check in here occasionally! And hope your family is doing well in Dauphin.
- Laura in PA and NJ
62. weathernewbie
6:23 PM GMT on February 08, 201761. Zachary Labe
6:28 PM GMT on August 31, 201660. Zachary Labe
11:11 PM GMT on August 20, 201659. Zachary Labe
11:23 PM GMT on July 21, 201657. Zachary Labe
9:58 PM GMT on June 09, 2016Hi Dabbio! Sorry for the late response. It is an interesting question that is getting a lot of attention in the meteorological field. While a sweeping generalization, I think there is an age element for the responses to this type of question in arguing the importance of humans in forecasting. Older generations support the constant need for humans in forecasting, while younger argue that computer model forecast skill is improving so dramatically that the need becomes a bit more hazy.
I argue a bit more in the later. We are seeing advances in both global models (coarse resolution, long-term predictions) and high resolution models (mesoscale processes, short-term predictions). We now have models that substantially improve simulations of convective events such as mesoscale convective systems or super cellular development. But there are certainly model errors. And another boundary in this debate is that computers can't really effectively communicate weather predictions like humans.
I think we are going to continue to see humans play more of a role in weather communication rather than forecasting. For the time being, yes, there is still a need for human interpretation and forecast skill, but I think it is beginning to wane. It is remarkable to see how accurate the high resolution, convectively-parameterized models can predict the location and timing of severe weather events... sometimes kinda scary-good.
56. Dabbio
7:30 PM GMT on June 06, 2016Hoping that all has gone well with you through this school year. We really miss you, but look forward to learning more about your accomplishments as time goes by.
I had an inquiry from my son-in-law that I hoped might stimulate some DIM (Deep Inner Meaning) from you. I am doubtful of what his quote portends, as I know from your forecasts that there are a host of non-computed factors that you used in your amazingly accurate near term/meso-scale forecasts. Would appreciate any comment on what he sent me:
http://arstechnica.com/science/2016/06/with-iphon es-and-computer-models-do-we-still-need-weather-fo recasters/
Link
Quote:
"""
Numerical weather prediction improved dramatically, especially since
the 1970s. An analysis in Nature, published in 2015, found that
forecast skill in the 3- to 10- day range has increased by about one
day per decade. That is, a 6-day forecast today is as accurate as a
5-day forecast a decade ago. And this improvement shows no sign of
slowing down.
"""
IN particular, Zachary, I was doubtful because some of the important weather phenomena, such as how much storminess an actual front will stir up in the final minutes, or whether and where a particular tornado will form, seem all fairly unpredictable to me. We seem to be able to identify general conditions, but not particular events.
Kind regards,
David A. Burack
55. BaltimoreBrian
10:57 PM GMT on April 14, 2016Greenland's Ice Sheet Is Melting So Fast Right Now, Scientists Thought It Was an Error
Some followup from Neven:
Greenland under early pressure too Quote from the article:
** It seems 2012 saw an even earlier and more widespread melting event, although I'm not sure if this NSIDC graph (found here) can be compared directly to the DMI graph:
53. Zachary Labe
6:47 PM GMT on February 25, 201651. Astrometeor
4:38 AM GMT on January 24, 2016Phooey, grandparents got more than I did.
26.7" official at Millersville University.
50. Zachary Labe
3:35 AM GMT on January 24, 201649. Zachary Labe
2:47 AM GMT on January 24, 2016Thank you! Enjoy the storm!!
48. weathernewbie
11:51 PM GMT on January 23, 2016- Laura
47. Zachary Labe
6:32 PM GMT on January 23, 2016Wow, enjoy it! Sounds like an amazing storm for the Lower Susquehanna Valley with already two feet for most areas!
46. Astrometeor
4:38 PM GMT on January 23, 2016I for one have never seen this amount of snow fall all at once. I've seen 3' deep snowpack, but that was already present when I arrived on site. There's snow piling up on my university window. Pretty low visibility, but the winds haven't been present as was forecast. But the snow is.
45. Zachary Labe
7:47 AM GMT on January 23, 2016Ah thank you! I surely am missing this one as it is now looking like potentially one of Harrisburg's largest snow storms on record. I miss the fun blogging days back in the winter of 2009-2010. Currently, I have my windows open here taking in the sea breeze haha.
44. Hoynieva
5:13 AM GMT on January 23, 2016This is looking like one for the record books for many parts of the mid-atlantic.
Be well, and enjoy the Cali life - doesn't get much better than that in this country, in my admittedly biased opinion.
43. Zachary Labe
3:46 AM GMT on January 13, 2016Haha thank you! And yes, I think I will always like that name ;) I think I will be definitely coming back east for a postdoc; I miss my four seasons too much. I wish I had more time for blogs again on here... maybe one of these days. But for now most of my posts are on Twitter (@ZLabe) due to the short and sweet 140 character messages haha
42. weathernewbie
10:49 PM GMT on January 12, 2016A question from one of your early friends here... Can we still call a distinguished UC scholar "Blizz" around here?
Laura in Princeton, NJ (formerly from Bucks County, PA)
P.S. Maybe Princeton for a post doc?
41. Zachary Labe
4:37 PM GMT on January 01, 201640. originalLIT
6:22 PM GMT on December 25, 201539. Zachary Labe
4:41 PM GMT on December 25, 201538. Zachary Labe
6:40 PM GMT on November 26, 201537. listenerVT
4:29 AM GMT on November 02, 2015We got snow here in NW VT on the 18th. Great fun!
36. Zachary Labe
4:06 AM GMT on October 31, 201535. Zachary Labe
1:32 AM GMT on October 19, 201534. Astrometeor
12:54 AM GMT on October 19, 201533. TheRasberryPatch
6:20 PM GMT on October 18, 201532. Pcroton
5:33 PM GMT on October 17, 2015criteria for winter storm watches/warnings and winter weather advisories in western
portions of chester county, pennsylvania (forecast zone paz101) for the upcoming 2015-
16 winter. the previous 12- (24-) hour snowfall criteria for a winter storm
watch/warnings in western chester county of 6 (8) inches will lower to 5 (7) inches for
the upcoming winter. similarly, the previous 12-hour snowfall criteria for a winter
weather advisory of 3 inches will lower to 2 inches in paz101.
the above changes to the western part of chester county allows for better inter-office
coordination with the national weather service forecast office in state college,
pennsylvania (ctp) and avoids public confusion across the eastern/western county zone
split in chester county. ctp, who is responsible for winter weather watches, warning
and advisories for the lower susquehanna region, has made the same criteria changes
effective this upcoming winter for lancaster county, the county that borders chester
county to the west
31. Pcroton
8:26 PM GMT on October 16, 2015As we all know we never quite know what to expect until it's on our doorstep. I always feel that until late to mid December when you see the first winter jet setting up you're not entirely sure where to draw the frozen/non-frozen lines. Then the same goes for the second jet setup after the "january thaw".
That being said...it's very difficult to forecast against the probabilities that such a strong El Nino plays into. Let alone one of this caliber..of which has it's twin to the north. We don't know the effect of all the additional warmer water. When we see it we'll know.
But those saying toss El Nino out the window and forecast a cold snow North East - because it's happened before in El Nino years - apparently are either forgetting to, or purposely leaving out, that such an assumption is only plausible during weak to somewhat moderate events. Those, yeah, we can be a toss up out east. Anywhere from textbook to contradictory results.
But in strong events, let alone the "super" events if you will, the probability of textbook dominant pattern conditions out east are quite very high.
And then there's always the keyhole event, the one that sneaks into the pattern, like our 72hr cold snap this weekend. You never can forecast one of those. If one times just right this winter - it could produce a strong coastal snow storm - one of which would equal or exceed Mid-Atlantic seasonal snowfall averages in one fell swoop.
But that still to me wouldn't be verification of "toss el nino out of the winter discussion" if the rest of winter is 50s and bland. It's just an unforseen keyhole event. The "Hurricane Andrew" if you will.
As always with weather we'll see. And when we see we will adjust.
30. Zachary Labe
2:54 PM GMT on October 14, 2015These are great points! I keep reading about people bashing those who don't include other signals/teleconnections into their winter forecasts. While yes important, this El Nino is entering such strong territory that its forcing is more likely to dominate the system in respect to other +ENSO events.
29. Pcroton
1:30 PM GMT on October 07, 2015The Euro did have the Mid-Atlantic capture scenario before any others and before it shifted to the east solution though. So it began the hysteria. Had it never shown that...then maybe we'd be able to really say it nailed it. It was the first to go right and be steady there I'll give it that but it wasn't flawless.
Also it's scores dumped as well during the period...likely tied to those few earlier runs (180hr-ish range) that showed the big Mid-Atlantic hit - while ironically all other models were out to sea in that short window.
Truly I think there's an issue in our observational data and data collection that's being fed into the models. Something has certainly changed and/or worsened over the past year or so. It's gotten far worse with guidance this past year. I think we're seeing a continued failure of observational networks and less balloon launches worldwide and it's taking it's toll. Failing buoys without repair, you name it.
Also the GFS Upgrade is a WORSE PERFORMING MODEL than the previous GFS it replaced in the last year. It's a joke.
...Here's the 2014 to 2015 SST Anomaly comparison. Some blowhards still trying to say El Nino isn't going to factor into the east coast winter weather. "I heard that last year" seems to be the common thread of ill science.
Yah, gee, identical! Can hardly tell the difference!
*sigh*
28. Pcroton
2:01 PM GMT on October 04, 201527. listenerVT
3:30 AM GMT on October 04, 201526. TheRasberryPatch
1:58 AM GMT on October 02, 2015That is great news about the hurricane modeling East
25. Zachary Labe
7:58 PM GMT on October 01, 201524. TheRasberryPatch
7:10 PM GMT on September 30, 2015Joaquin will be interesting. I heard maybe another Sandy track
23. Zachary Labe
3:19 PM GMT on September 30, 201522. Zachary Labe
3:18 PM GMT on September 30, 201521. Rittenhouse
12:36 PM GMT on September 30, 2015If we do get an arctic outbreak in November, looks like the Great Lakes are in for one heck of a lake effect event though.
Nice to see this blog being updated again, especially with Joaquin threatening the Northeast.
20. Pcroton
4:40 PM GMT on September 28, 2015Please post 'em if you can find some good higher resolution anomaly maps for the Lakes.
I also wonder if this is going to lead to some impressive lake effect streamers beyond the usual time frames for those events.
19. Zachary Labe
2:51 PM GMT on September 26, 201518. Pcroton
7:42 PM GMT on September 25, 201517. Zachary Labe
7:40 PM GMT on September 25, 2015(Fairbanks -- 3-4" so far)