Lake Effect Very Likely Tonight

 Conditions are excellent for a lake effect event tonight and early tomorrow: cold air, relatively warm lake water temps, decent moisture and instability.  It’s the weather nerd in me that is fascinated to see how this develops tonight.  The lake effect band may start close enough to the Cottonwoods to drop more snow up the canyons, however, I’m thinking it may migrate away from the Cottonwoods and closer to the Oquirrhs by later tonight.  It will be interesting to see how this lake effect band develops. If we can get it just right, we could see decent accumulations.

Latest Snow Pack Numbers In Utah

Lets all hope for a stellar March as we are about 80% of normal in northern Utah.

Click here for the latest Snow Pack numbers in Utah

Winter Driving Conditions Expected Thursday Eve.-Friday

There is a good chance of Very Dangerous Road Conditions for the Thursday evening commute as well as Friday morning's, below is a graphic from UDOT concerning this potential!

 

Statewide Road Snow Event
Thursday and Friday

 

Snow amounts: Right now computer models are all over the place with regards to amounts, i will go with  4-8"+ in the valleys with the possabilty of much more if the DLE (dreaded lake effect ) sets up over a certain area, Benchs 6-12"+ and Mountains 1-2'+. Enjoy

Fresh Pow for Christmas in Utah

      Systems continue to push into the west coast as the large parent low spins off the Pac NW coastline. Everything still on track with previous forecast. Main change is that short-range models are now within range and bringing in the details, so we have greater confidence in snowfall amounts. We will have breezy conditions today with a warm southwesterly flow ahead of the approaching systems. This flow should scour out the cold pools (inversions) in the valleys and allow them to warm up. Clouds should also be on the increase this afternoon
.
      Tonight we have the first weak wave bring mostly mountain snow showers after about midnight. This will primarily affect the mountains north of I-80 and could bring 1-3″ of fresh snow for tomorrow. We will then see a break in the action Sunday afternoon / evening as the next, more potent, system enters the area.
This stronger system will bring snow to the area late Sunday night and the snow should continue all day on Monday before tapering off on Monday night. The system is currently progged to track perfectly to bring the entire Wasatch a good period of both frontal and post-frontal snowfall. This is by no means a major snowfall for the Wasatch, but everything looks good for a decent period of snow. The lower valleys might start as rain or rain/snow mix early Monday morning before changing to all snow as the front approaches late Monday morning. Valleys can expect 1-4″ of snow. The Wasatch should see .75-1.25″ of QPF and average snow ratios of 15:1 — this translates to about 10-18″ of snow for the high elevations. Not too shabby! The other concern will be travel conditions around the state, with Christmas eve being a busy travel day this could hamper travel to grandmas house. As of now this is what  UDOT is saying: ****Please check back Saturday afternoon for road weather impacts as a stronger storm moves through Utah Sunday evening through Monday (Christmas Eve).  Valley routes and the I-15 corridor are expected to see periods of light road snow while mountain routes will see moderate accumulations of road snow Sunday evening through Monday (Christmas Eve).***Click Here to go to UDOT's Road Weather Alerts

Here is the latest model-generated snowfall forecast for the Western CONUS through Christmas day:



      We should clear out on Christmas Day for blue bird conditions. Wednesday we’ll see the next system approach with snow likely Wednesday night-Thursday night, perhaps lasting to Friday. At this time this looks like a moderate storm. Great news for all the holiday skiers who are traveling to Utah for some freshies. But it could cause some travel headaches.

     The Cottonwoods and PC continue to do alright this year and are just above average snowpack, but the Northern Wasatch is struggling at less than 50% of normal in places so lets hope we can get some good snows going in their direction as well.

Plenty of Snow in Utah, More to come !

   WOW what a storm a Powder day on tap for sure!  Looks like the Cottonwoods have close to a foot and Park City area  received 5-10″. Wasatch front Valleys have seen anywhere between 1"-6" and benches between 4"-12". And it is still snowing . . Additional accumulations of 1-3″ in the Cottonwoods and PC is likely. Here’s a look at the Snowbird Snowcam (which measures up to 16″):

Pic. courtesy  Sheryn Shaw on Saturday morning

  
Our next storm will arrive on Sunday and as i stated in my last post, we will have to watch this one and of course it looks a little stronger than before,  it still looks like it will move in for Sunday through Monday. This is an advection precipitation event and favors the Northern Wasatch. NWS has hoisted a Winter Storm Watch already to highlight this. This system looks much better now than it did the other day, so we’re feeling optimistic. Another 10-20″ can be expected for Sunday-Monday in the mountains with up to 2 feet in favored locations north of I-80. Wasatch front Valleys should receive another 1"-3" + ,benches should receive 2"-5" +. Lots of Snow! Monday should be an awesome powder day!

      The next system moves in late Tuesday and drags a front through the area early Wednesday morning. This system is fairly potent as well as very cold. There will be potential for lake effect snow behind the front on Wednesday.  We’re looking at potential for additional significant accumulations of 1'-2' + for the Wasatch mountains with wasatch front  valleys 6"+ and benches 12", hopefully the models do not flip flop on us and it produces a BIG snow event, Keep your Fingers Crossed! 

     After Wednesday it looks like we’ll have at least a 4 day break with the possibility of urban Fog, next chance for snow will be Christmas eve or Christmas day. But let’s focus on the a very snowy short term for now!

Powder Days Ahead

Who is ready for some more POW

     Tonight-Saturday the Wasatch mountains should receive 6-12" of snow and the valleys might squeeze out 2" while the benches might receive 4".

      Sunday -Sunday night was once a pretty good looking storm according to models a few days back, now most likely a warm advection type storm, which means no front crossing the area, so looks like the Wasatch will receive another 4"-8" of snow and the valleys maybe another 2"-3" and benches 3"-5" Poss. more will have to watch this one.

Tuesday-Wednesday still looks like a very potent storm for the area, a strong cold front blasts thru around the evening commute tuesday, might have to watch this one as temps will fall in the 20's behind the front so accumulating  road snow and ice will be a good bet, right now i am thinking 1'-2' + for the Wasatch mountains with valleys 6"+ and benches 12"+.  Plus there is a chance of DLE (dreaded lake effect ) Wednesday morning.

If you have not tuned up the Snow blower now is the time!




 


Stay tuned will update tomorrow! 

White Christmas ?

   

   Tomorrow will be clear but winds will be on the increase ahead of the next system.  This system is a cutoff low that will drop down the west coast on Wed before ejecting inland over So. Cal, N. Arizona and S. Utah on Thursday and Friday.  This will bring high elevation snow to S. Utah where they desperately need it.  The Wasatch will just see a chance for mountain snow showers on Thurs and Friday.  A secondary wave will drop in from the northwest Friday night and give Northern Utah a chance for more widespread snowfall.  Still, amounts should be light with just a few inches in the mountains.

      Saturday should be the break in the action before a larger, colder trough enters the area on Sunday.  This storm right now is timing for a late Sunday through Monday.  Still questions about its overall strength but it has potential to be decent.  We’ll continue to watch it.  Models agree on a break for Tuesday of next week with another system dropping in on Wednesday with another system possible for the weekend leading up to Christmas.  Definitely has the potential to be a great little pattern for us in Utah and throughout the Western U.S.
                 
         Below are forecast models for Sunday the 16th and Wednesday the 19th, and i also put Christmas Day in there also, this is way far out there but models for the last 3 days are showing a storm for Christmas, let keep are fingers crossed and hope it brings us a white one!

Sunday the 16th @ 12pm

Sunday the 16th @ 6pm

Wednesday the 19 @ 12pm

Christmas Day @ 12pm

Utah to continue to receive some POW!

 A low pressure system will cutoff from the general flow and drop down the west coast over the next couple days before ejecting inland.  It will have a lot of energy and moisture to work with, but looks like it will track over northern Arizona.  A bummer for us in the Wasatch as we’ll likely see very little snow from this, but good news for the mountains of Southern Utah and Northern AZ that really need some snow.

Attention then turns to potentially stronger systems that may bring some great skiing and riding to the area leading up to Christmas (or the end of the world, depending on your perspective).  The eastern pacific ridge retrogrades westward, allowing for the storm door to open up for the west coast and areas inland (Utah).  The first of these systems is being handled differently by each model. The GFS is weaker with the system and keeps it mostly in the northwest with just a few showers for northern Utah this weekend, it does eventually drop the system into the Great Basin, but not until early next week.  The Euro and GEM are similar with the strength position of the system, but differ on general timing of the heaviest precip.  The GEM wants to bring heavy snow to the area starting  late Saturday, while the EC holds off until Sunday.  Both solutions are stronger and farther south with the system than the GFS.  General consensus in the meteorology world is that the EC and GEM are the better models with this particular feature based on better ensemble support and a better recent track record.  But the stubbornness of the GFS to come around over the past few days keeps confidence low.  We believe that we have a decent shot at a  significant storm on approximately Sunday the 16th if these trends hold.  Snow levels will likely be at valley floors for this system as well.  I told you all to just hang on till mid-month… fortunately mother nature provided some frequent small storms to make the wait a bit easier.

The synopsis is we will have a break Tuesday and Wednesday, a chance for light snow Thurs/Fri as the cutoff low tracks to our south, and then a chance for a better storm this weekend.
Long-range outlook still looking good with the progressive pattern continuing and systems dropping in for the next couple weeks.  We are either going to have a nice snowy end of the world on the 21st or a great holiday ski season.   I’m okay with either.

We’ll keep you posted this week on how the weekend storm is looking….

Promising Signs of a Much Needed Pattern Change

      Snow has already started falling lightly in many mountain areas. Should be off and on but picking up throughout the day with the best chance for accumulations occurring later tonight. Just a few inches in the Wasatch with up to 6″ in areas favored by a northwest flow like the Cottonwoods. Just not enough moisture to work with for it to be anything major.

     Another even weaker system on Monday night will freshen things up with another 1-4″ in the Wasatch… Wednesday’s system is looking stronger but is now progged by all major models to drop down the West coast and move inland tracking over southern Utah. So the Wasatch will likely only see another round of light accumulations.
The whole while it will be cold with modest warming between waves. This will allow for good snow-making so resorts that need to supplement their bases can do so.

     The next week will be nice in that we’ll see frequent systems but disappointing as they are all weak. As a forecaster, it’s Week 2 that’s looking especially promising starting around mid-month (next weekend). It’s still far off, but there’s been a lot of model consistency for cold, stronger storms to start moving into the Pacific Northwest and dropping into the Great Basin. Stick with us over the next week, enjoy these little storms, and we’ll keep you posted on the status of the big boys. Keep the good vibes going… I don’t think I could take another backtracking of the models.

   Below are current model runs of projected water amounts!  

Saturday the 15th

Sunday the 16th

 

Tuesday the 18th

Look's like December will Roar in here like a Lion!

        Today will be fair and mild with increasing clouds and breezes later in the day. Tomorrow morning we’ll be brushed by a weak system moving by to our north and east. Only a slight chance for showers in the Wasatch tomorrow morning with the highest chances close to the Idaho border. Snow levels will be relatively high near 7,000 ft and we don’t expect anything more than a dusting anywhere. Temps will drop by 10 degrees or so behind the front on Monday, but will warm up as a ridge rebuilds through Wednesday.

     

       Attention then turns to the next, more significant system dropping down from the Gulf of AK. It will mostly affect coastal areas of California, Oregon and Washington through the end of the work week. We’ll be under a moist southwest flow so it is possible to see a couple showers on Thursday/Friday, but it won’t be until later in the day on Saturday (Dec 1) that the system will really start to move inland. Still a lot of questions as to the overall strength and how well this system will hold together as it moves across the Great Basin, but we think it definitely has potential to be significant. Snow levels will likely be well above the valley floors so it could be another good base-building wet snow for the resorts. Lots of details still have to be worked out but next weekend looks to be our return to active weather. Stay tuned . . . 

Saturday Dec. 1st

Sunday Dec. 2nd

Monday Dec. 3rd

 CLICK HERE FOR LATEST COMPUTER MODEL

The Graphs below are from the Climate Prediction Center, they are showing Utah having a 40-50% chance of precipitation between Nov.30th-Dec.7th

Add caption

       

Old Man Winter Will Be Busting Down The Door

For the last 5 days or so models have been showing the front entering Northern Utah late Thursday evening and moving the SLC area around midnight. Now both the NAM and GFS are showing a delay in the onset of precipitation until late morning Friday. Not a ton of moisture with the initial front but could see a brief period of moderate to heavy snow in the mountains and lighter snow in the valley during the day Friday. There may be a break after the front on Friday evening before the instability and moisture associated with the cold pool move into the area. Friday night and Saturday we’ll see the best dynamics and the best orographics for widespread moderate to heavy snowfall. There will be a good chance for lake enhancement or a lake effect band downwind of the lake. Best guess right now would be east-southeast of the lake. Over southern Davis County and Northern Salt lake County toward Park City. We’ll have to monitor the lake effect situation as we get closer as it is notoriously difficult to forecast.

When we look at the two aspects of this system, the front and instability behind the front, we can split the system into two separate parts to make our snowfall predictions. The initial front on Friday looks like it will put down 4-8″ for the mountains and only a couple inches in the valleys. Then the cold pool on Saturday has potential to drop up to 6″ in the valleys with more than that possible under lake effect band if one sets up. The mountains will likely see over a foot of snow on Friday night-Saturday night time frame. There isn’t incredible moisture associated with the system. But the direction of the flow aloft will allow for good orographics and the cold air will create very high snow:water ratios so just 1 inch of liquid qpf will likely yield 18 inches of snow.

With all that in mind, by midday Sunday, we expect the following totals:
1-2 feet above 7,000 ft. (with possibly more in orographically favored areas or under lake effect band)
6-12 inches in mountain valleys / high benches of Wasatch Front
Up to 6″ on valley floors

Next week is still a little unclear but it’s looking like we may be clipped by another system mid-week however it looks weaker/warmer. We’ll keep our focus on the storm at hand for now.

Snow, and lots of it, looking likely late this week!

Models have been in fairly good agreement for several days but confidence continues to increase as we move closer to the event as the global models are less likely to back track from here on out. After a few more warm, dry days, the weather will change dramatically to a very cold, snowy pattern. Timing still looks like the initial front will move through Thursday night and snow levels will drop Friday to all valley floors. Good orographics and decent moisture behind the front will allow for snow to continue in the mountains and on and off in the valleys for much of Friday night and Saturday. Lake effect snow is also a very good bet with cold, moist air traveling over the relatively warm GSL–this is very hard to forecast so we’ll have to wait until we get closer before we make any exact lake effect forecasts, but be aware that the possibility exists for it.

Later we’ll have a full update where we’ll take a first look at potential snowfall totals. Hint: they have potential to be significant for all elevations.

Looking like we may see a couple more systems trying to dive into the area next week as well. The ski areas should open on time at least!

CPC showing 50% chance of above normal precip for Nov 9th-13th.

November Outlook

 

It is the dawn of a new month and an exciting one at that — November is generally when the Wasatch range starts building its snowpack and ski resorts throughout the area start turning their lifts. October was a month of teasers for the most part with the occasional dusting high up in the first two weeks of the month and then the third week we saw our first major system. That system favored the Northern Wasatch so PowMow, Snowbasin, and Wolf Mountain all received enough snow (40″ +) put down what will likely be a permanent base. It also allowed for some of the die hards to get up there for the first turns of the season. However the Central and Southern Wasatch only saw 8-14″, and after a couple weeks of warm, dry weather, they will have to start from scratch.

Just had a look at the latest12z model suite (computer models)and they've been consistent on a storm for next weekend that has potential to be a significant snow producer for the Wasatch and should bring some snow to valley floors as well, including another shot at lake effect snow. There are still questions as to the exact track and strength of the system. EC is a little farther west with the system, bringing the best dynamics to the Cascades and the Sierra Nevada. The GFS drops it into the Great Basin with more favorable dynamics for Utah. Either way, we should see some snow in the ‘Satch with high snow:water ratios, so it could pile up rather quickly, the cold airmass will allow for resorts to make snow around the clock starting on Friday. Timing currently looks like frontal passage late Thursday night, so Thursday will likely be mild and windy. Friday we’ll see the bulk of the precipitation but it may continue right into Saturday.


The rest of November becomes little more than guesswork, as any meteorologist worth their salt will tell you that long-range forecasting is little more than speculation. But it’s worth looking at. My best estimate based on a combination of upstream factors and the MJO is that we will have a dry first week of November (certain), stormy second week (likely), dryer third week (maybe?), and a return to unsettled weather for the last week of the month (who knows!). Again, this is just an educated guess so don’t go planning your Thanksgiving travel plans based on what I just said. Everything beyond about the 10th of November is totally up in the air, so to speak. What is encouraging is that last November we were sitting on the east side of blocking ridge that didn’t budge until January, and the only snow we saw early in the season was from weak systems diving down the east side of the ridge and clipping the area…. This year, however, there is still an Eastern Pacific high but it isn’t nearly as stubborn and is allowing for more progressive systems to enter the area. So hopefully we won’t fall into the same pattern that plagued us for so much of last season.
So there you have it! A first look at the month of November.

Keep your fingers crossed and we’ll update daily as we approach next week’s pattern change.

Old Man Winter is knocking on the door . . .

            Everything is starting to look a little clearer through at least Wednesday of the upcoming week.  The Wasatch and adjacent Wasatch Front will see its first real winter pattern this week with one large Low sending in reinforcing impulses every 24 hours starting today.Click here for latest western satellite.     Today’s impulse will do little more than bring in some clouds, winds, and slightly cooler temps.  Tomorrow’s will be a little stronger with a slight chance for showers.  The first real threat for accumulating snowfall will start on Monday in the mountains with rain showers in the valleys below 6,000 ft.  At this time it looks like rain and snow will increase in intensity on Monday into Monday night before clearing out Tuesday morning a bit before a reinforcing wave of energy picks things up a bit on Tuesday evening through Wednesday.  This latter impulse could be strong and cold enough to bring snow levels down to SLC valley floors, or at the very least, to the bench locations.

 Also of note is that the GSL temp is very warm which might bring us a lake effect storm! Here is the latest info for the lake:

WRF-NMM LAKE TEMPERATURE CALCULATION
LAST UPDATE: 05:45 UTC 10/20/2012
WEEKLY AVERAGED AVHRR-DERIVED TEMPERATURES       
7-DAY MEAN ENDING 10/15/2012
NORTH ARM
16.28 C
SOUTH ARM
15.77 C

CLIMATOLOGICAL LAKE TEMPERATURE                 
13.5 C
LAKE TEMPERATURE USED IN WRF
14.7 C

TLAKE EDITED IN WRF-NMM AT: 05:45:06 UTC 10/20/2012

As you can see the Avg water temp this time of year is 13.5 c (56.3 F) but with the HOT summer we had it is sitting at a mean of 16.0 (60.8). if we drop to -1c (30.1 F) we will be cold enough for lake enhanced or lake effect squalls, but there is a few more ingredients needed to make this happen as described below.

 

 Lake-effect and lake-enhanced snow is more complicated than just cold air within northwest flow moving over the warmer Great Salt Lake. The necessary ingredients include sufficient over-lake temperature differential (i.e. greater than 17C from the surface to 10,000 ft MSL or 700 mb), sufficient distance of air flowing across the lake (northwest or north flow provides this across the longer portion of the Great Salt Lake ), minimal change of wind speed or direction in the boundary layer, deeply unstable boundary layer (top layer above 600 mb level preferred for sufficient convective growth), adequate steering flow to develop banding, and over-water surface convergence which is often driven by a land breeze circulation under radiational cooling at night (air flowing toward the warmer water from the colder surrounding land). The lake bands can be further enhanced when they are sufficiently deep and extend well inland resulting in upslope flow of the moist air along the west slope of the Wasatch Range. For a given event the ingredients for lake-effect and lake-enhanced precipitation varies with respect to the potential for generating snow. This will determine if a lake band or lake enhanced area of precipitation will develop and how long and intense the snowfall will be.

Click here for latest future radar loop

 La Crosse Technology Solar Professional Weather Center (Google Affiliate Ad)

Possible Major pattern change

After not checking the models for the last 48 hours, I was excited to see that the latest 18z run of the GFS and the latest run of the Euro both show a potential major pattern shift for next week.   We generally take these long range models with a grain of salt as anything beyond 10 days is very unreliable, but it was worth noting.  Well it seems that this time the charts were on to something.  Models show a much colder, more organized system diving into the Great Basin late next weekend/early next week.  It is still very early, but this is the type of winter storm that could bring snow all the way down to the lower valleys with decent, lasting snowfall for the mountains.  The latest versions of the CFSv2 continue to indicate this pattern change in today’s run.  Here is the current forecast for the week of Oct 21-27:

As you can see, it depicts a deep moisture tap taking aim at the entire West Coast of the U.S., the type of pattern that is conducive for good Utah snowfall.  It is still very early to get into any details but it does seem as if there may be a series of systems to affect the area after the initial system.  Something to keep an eye on for sure, as it could be the type of pattern that goes a long way to getting the Utah ski season underway.

However this ends up playing out, we’ll keep you informed.  Hopefully the models continue with this trend instead of backtracking as they did so often last year. Right now, we are leaning towards the colder, wetter solution. 18z GFS seems to reflect this as it trended slightly farther south than previous runs. Of note, if the colder solution verifies, we could be looking at snow down to SLC valley floors–lake effect snow is also a distinct possibility as GSL surface temps are still relatively warm. Still very early but this is an exciting trend that could go a long way to getting us all on the mountain. Cross your fingers that the models don’t backtrack.