The last few weeks have been dry. But, the Climate Prediction Center has a roar in their outlooks. This seems possible with a potential moisture surge from a tropical system coming across Northern Mexico and Texas. Also, another chance for a big East Coast storm, Katia, is on tap for the not to distant future.
I recorded a whopping 1.71 inches of rain by my electronic and manual rain gauges yesterday. I think this is the first time they have matched.
We’ll see as more people post their rainfall from yesterday, but it looks like it was a wet one for most of us. The National Weather Service reported 1.08 inches, just 2 hundredths of an inch short of the 1.1o inch record. According to them, that puts us a little over half an inch above average. Which means that in a single day, we went from about half an inch below average, to half an inch above average.
This morning the models are looking wet after Wednesday. The forecasts and models for the next couple days are dryer than yesterday, but things should start back up late in the week.
The storm track for the last few weeks has been more to the south than I would have expected. Temperatures this morning are far below normal and tonight the temperature for the Pinecone Drop will be significantly below zero. Temperatures across the Southeastern US, much of the Caribbean and most of Europe have been chilly, too. This can be attributed to the the negative phase of the Arctic Oscillation(AO) that has been in place since the middle of November.
The key characteristics of the negative phase are high pressure at high latitudes and lower pressure to the south near 45 degrees. This brings warmer than normal conditions to some places like Greenland, and colder temperatures like we have seen in the Eastern US. It is also responsible for the shift of the Western US storm track to the south, into Arizona. The question is: “Will it last?”
As I pointed out in the fall, I thought we would be moving toward a dry and potentially warm winter. December and November both started that way and shifted along the way. Here is the GFS model outlook for the AO.
The Climate Prediction Center has been fairly consistent in their outlook for the Southwest to be warm and dry this winter, even in their 6-14 day outlooks. But, with this outlook for a mostly negative AO, they seem to be changing their tune. Here are their 6-10 and 8-14 day outlooks.
In this outlook from yesterday afternoon, they are seeing a persistent storm pattern similar to the last couple weeks. What’s odd is that this morning just about every model has significantly altered the outlook to little chance of significant snow for the next couple weeks. This is a big shift. Joe Bastardi, at AccuWeather, seems to believe that this pattern is going to come to an end and we will see a return to conditions like we had in Early December.
Yesterday, I thought we were looking at a persistent storm pattern. Today, I am not so sure. But, I think the next few model runs will tell the tale. With the cooling in the North Atlantic. We could see more of an average overall winter for Flagstaff.
The forecasts and models continue to be all over the place this morning. It looks like we will get fairly persistent precipitation all day, but how much will be snow and how much will be rain is up in the air. The weather service shows minimal accumulations in their text forecasts for many areas. But, they have this graphic posted on their site:
And most models are still showing a reasonable shot at another quarter to 3/4′s of an inches of water precipitation(some even more). But, the snow level outlook is right around 6600-6700 feet. So that will we will probably bounce back and forth between rain and snow until tonight.
Looking further out, there is an on-going chance of rain and snow through the holidays. It will all depends on the the direction of the storm pump. This current storm seems to have started with the pump directed even to the south of us.
Yesterday was beautiful as promised. The outlook is up in the air
RECORD EVENT REPORT...CORRECTED NATIONAL WEATHER SERVICE FLAGSTAFF, AZ 818 PM MST MON DEC 13 2010 ...RECORD HIGH TEMPERATURES FOR NORTHERN ARIZONA ON DEC 13 2010... CITY NEW HIGH PREVIOUS RECORD/YEAR BELLEMONT 65 57 IN 2004 COTTONWOOD-TUZIGOOT NM 76 70 IN 1996 FLAGSTAFF 67 66 IN 1921 FORT VALLEY 65 64 IN 1950 GREER 64 59 IN 2004 HEBER 68 67 IN 1969 NAVAJO NM 56 54 IN 1962 PAYSON 69 68 IN 1969 SELIGMAN 73 70 IN 1950 SHOW LOW 67 63 IN 2004 GRAND CANYON SOUTH RIM 63 62 IN 2004 WALNUT CANYON 60 57 IN 2004 THE HIGH TEMPERATURE AT THE SEDONA AIRPORT TODAY REACHED 70 DEGREES. THE OFFICIAL RECORD HIGH FOR TODAY IS 70 DEGREES...WHICH WAS SET AT THE RANGER STATION IN 2004. ...RECORD HIGH TEMPERATURES FOR NORTHERN ARIZONA ON DEC 12 2010... CITY NEW HIGH PREVIOUS RECORD/YEAR BELLEMONT 60 60 IN 2004 COTTONWOOD-TUZIGOOT NM 75 70 IN 1996 THESE RECORDS ARE PRELIMINARY PENDING OFFICIAL REPORTS.
The outlook is a little uncertain. Just as the North American Mesoscale (NAM) model has firmed up on a strong storm hitting the area on Thursday, the National Weather Service has moved to a fairly light 1-2 inches of snow in their forecast. Accuweather has dropped snow from their forecast. The NOGAPs model shows only a small amount of precipitation. The GFS Model shows light amounts in Northern Arizona, with heavier amounts to the south. So, which is right? I think it mostly depends on the positions of the High and Low pressure systems off the Pacific Coast. I think the graphic below captures the situation. If the pump isn’t directed at us, we get very little. If it is directed at us we get a lot.
Check Out Ken Clark’s Blog at AccuWeather. He notes the potential pineapple connection. Very nice discussion and images.
It looks like the persistent high pressure system off the coast of California and the Baja Peninsula is going to move south as a major low pressure system stations itself in the Gulf of Alaska. The opposite rotations of the two systems is going to open up a storm door that current looks to project out through Christmas. The high and low pressure systems will become a storm pump as their flows coincide in an easterly direction.
A series of troughs will be pushed through this door. Many of these will cross Northern Arizona. Each wave will bring cool temperatures and a chance for precipitation. Currently, the first wave will pass through our area from Wednesday evening to Friday morning. It looks to have only light moisture amounts with it. Looking longer, the start of next week could see over half an inch of water for the Northland.
How can you tell a change is on the way? You have an amazingly beautiful day like today is going to be. We all know it just can last. Enjoy it while you can.
Sorry folks, I’ve been in Japan for the last week and out of the loop as a result. Sorry the storm didn’t materialize while I was gone. It looks like there will be a couple chances for white stuff in the near future.
The normally conservative AccuWeather forecast has snow forecasted for the week of Christmas. Not just for a single day that week, but the entire week. In fact, they see the snow starting next Thursday and continuing through December 24. To some extent, his is reinforced by the GFS model which shows a strong system on a southerly track hitting Arizona on December 23. The Flagstaff forecast from the National Weather Service has a chance of snow next Thursday.
But, the high pressure off the coast of Southern California has been quite strong and unmovable of late. I am highly skeptical. But, my T-model shows a similar possibility for Christmas Week.
It’s been a while since I can remember a record breaking, winter time low. Yesterday the Flagstaff Airport reported -4 as the temperature. This broke a record set in 1975.
With that said, the rest of this week should be warmer and nice. My personal T-Model continues to show a good chance for a storm between Monday and Wednesday next week. The GFS model shows something weaker, more to the north and sooner. NOGAPS shows a good southern track, later and stronger.
Well, here is my T-Model outlook for Friday to Thursday, December 5-11.
This is a very novel and proprietary model. The key to it is my confidential set of inputs.
Given the inputs to the T-model, and current NOGAPS and NOAA computer models, it looks like there could be a good chance for a cut-off low pressure system to form off the coast of California next week and move over Northern Arizona. This could be a significant storm. However, cut-of low pressure systems are notoriously difficult to forecast.
On another note, if you read the Forecast Discussion from the National Weather Service, you should look for the discussion provided by Peterson. Here is one from this morning:
000 FXUS65 KFGZ 301028 AFDFGZ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 330 AM MST TUE NOV 30 2010 .SYNOPSIS...COLD AND DRY CONDITIONS WILL PERSIST TODAY BEFORE A WARMING TREND DEVELOPS FOR THE REMAINDER OF THE WEEK. && .DISCUSSION...LOW-LEVEL EASTERLY WINDS WILL PERSIST TODAY...ALTHOUGH THEY WILL BE QUITE LIGHT. THIS WILL KEEP COLDER AIR TRAPPED OVER MUCH OF NORTHEASTERN ARIZONA...INCLUDING THE NORTH-FACING SLOPES OF THE MOGOLLON RIM. THIS...COMBINED WITH A VERY COLD START TO THE DAY...WILL MAKE FOR ANOTHER AFTERNOON OF BELOW NORMAL TEMPERATURES. BY WEDNESDAY...THROUGH FRIDAY OR SATURDAY...HIGH PRESSURE WILL AMPLIFY OVER ARIZONA...WITH LOW-LEVEL WINDS BECOMING SOUTHWESTERLY. THIS WILL MAKE FOR A SUBSTANTIAL WARMING TREND AND CONTINUED DRY CONDITIONS. MODELS STILL HINTING AT THE NEXT SYSTEM BEING LATE IN THE WEEKEND...OR EARLY NEXT WEEK. STRENGTH...TIMING...AND LOCATION ARE ALL OVER THE PLACE...SO LOW POPS AND MODEST COOLING ARE ALL WE CAN REALLY GO WITH FOR NOW. && .AVIATION...FOR THE 12Z PACKAGE...VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD...WITH MOSTLY CLEAR SKIES...AND WINDS GENERALLY 10KT OR LESS. A FEW HIGHER GUSTS ARE POSSIBLE THIS AFTERNOON AT KFLG AND KGCN. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. $$ PUBLIC...........PETERSON
It’s snowing at a fairly good rate this morning. At 6:30 am, I already have about an inch of brand new white stuff. It looks like a little more moisture has made it to Northern Arizona with this storm. For Flagstaff, the National Weather Service is calling for 2-5 inches total from today into tonight.
From NOAA, one of their short-term, high resolution models shows significant potential for some areas, like the San Francisco Peaks. This model is an outlier. I think we will see a storm similar to other recent storms. 2-5 inches is probably about right.The real news will be the continued cold following the storm. Get ready for more single digit temperatures, and low snow levels. Sedona could see snow today!