Snow for San Franansisco! First time in 35 Years!

That's right. San Fransisco hasn't seen snow in 35 years but that streak will likely be coming to an end beginning tonight and into Friday.

A very cold and very unusual storm will be affecting the whole west coast for the next few days. A strong storm will move from the Pacific Northwest down the west coast and bring snowfall down to sea level in areas that never see it, including San Fransisco. If you know anything about weather on the west coast, specifically winter weather, you know that snowfall has everything to do with how elevated you are.

The mountains of eastern California, Washington and Oregon typically have very heavy snowfall totals in the winter. As do mountains in Western Nevada and Arizona. But these areas are situated 1500 feet above sea level.

While this next storm will give those areas plenty of snow as well (10-20 inches), it will be so strong and so cold that snowfall levels will drop down to 500 feet and it is anticipated that in some of the heavier precipitation bands, snow will be falling at such a strong rate that it will cut right through 500 feet and leave a coating on the sea level streets of San Fransisco! That should be a sight to see.

A coating of snow is one thing, but Las Vegas, yes the same Las Vegas that regularly hits 110 degrees in the summer, will see measurable snowfall from this system, in the order of about 1-3 inches. Something tells me that the outdoor pools will be closed this weekend.

What will be even worse for some people is the cold air that settles in over all of the west after this storm. Take a look at daytime highs in southern California on Saturday. LA may struggle to hit 50! San Diego too.

Wild weather indeed is in store for the country this weekend into next week. You can expect to hear about tornado outbreaks in the deep south as well as flooding concerns closer to home. These strong storms will continue to march across the country every few days. The next one for us will be tomorrow but as you can see below, the storm track is what we call and "inside runner". Meaning it cuts up the Appalachian Valley and gives heavy wet snow to the north and very heavy rainfall to us.


This type of track will be the trend for us for the near future, with no blocking high pressure in place to the north to help steer these storms to the coast. Expect the storm from the west coast to give us more soaking rainfall on Monday/Tuesday.

Many of you may be rejoicing that at least it is only rain and not snow but I remind you that we still have a very healthy snow pack throughout the region. Adding very heavy rain on top of that can lead to severe flooding. I don't see this as a big issue for Boston since most of our snow pack has melted already but if you travel just a little north and west of the city, here is where you will find the biggest concerns for severe flooding.

For now, remember to bring an umbrella with you tomorrow! Its going to be a soaker!

Get Ready For a Wild March

So today was nothing. Light snow, barley sticking to the street. All in all, about 1-3 inches fell over the area. If you are interested in more detail, totals are Here

Things will be tame for the next few days but man did it get cold tonight! Winds are whipping in from the northwest and with a clear sky, we get cold. Better than what is missing us to the south. Our friends in DC and the mid atlantic will finally get their snow storm, if you can call it that. Remember last year?

Baltimore 80 inches
Philly 78 inches
DC. 72 inches

Sound familiar? They weren't so "lucky" this year. But this is a bit of a surprise since DC was 70 degrees last week. Get used to these extremes.

Stormy weather is ahead for us. But it doesn't have to be all snow, as will probably be the case this Friday.

Week Ahead

High pressure to the North saves us from any really significant snowfall tonight into tomorrow. Maybe 1-2 inches but the sight of freshly fallen snow will likely bring back bad memories of 70 + inches of snow. Not to worry.

That same high pressure actually will give us a pretty nice week of weather, with temperatures moderating Tuesday through Thursday and plenty of sunshine. Stand in the direct sunlight at this time of year for a few minutes and you will actually start getting hot. Strong sun this time of year. Speaking of which....

Sun is going bonkers

After Thursday, all signs point to a inside track type of storm where the low pressure passes well west of Boston which leads to heavy rain. This looks like it starts the beginning of a return to a stormy pattern into the first week of March. Stay tuned!

Winter! Where Have You Gone??

Sun! Warm Temps!! We all must be dreaming. But fear not my friends, we could not be closer to reality. Welcome to 2011's version of winter halftime. These "thaws" are not uncommon, in fact, we usually have one much earlier than mid February. The lack of one this year is the reason for those huge snow piles.

Speaking of those snow piles, expect big melting to continue through today. Temperatures near or above 60 degrees for two straight days will put a big dent in the snow cover but it will not melt everything. That should re enforce the idea of just how much damn snow we had on the ground!

Of course, we know that these thaws do not last. We are entering the "battle zone month" of March, where we can see some pretty extreme temperature and weather swings in just a matter of hours. Many people are asking me if this is it for snowfall for the rest of the winter. I obviously do not know the answer to that but my gut feeling combined with NWS 2 week projections tell me no.

One thing we know about late winter into early spring is that there is a constant tug of war between warm air building in the south and increasing in strength with a stronger sun angle and longer days and retreating cold air which will take a while to moderate and very often does not give way to its warm friend very smoothly.

Where the battle lines are is where you will find storms. In fact, these late winter storms can be very strong. In general, the bigger the difference in air mass temperature, the stronger a storm will be.

In the past few weeks, we have benefited from a blocking high pressure to our north that has kept us cold (except for yesterday and today) but more importantly has kept us out of the path of storms. This will begin to change starting next week and this will mark the beginning of the battle between winter and spring. Want proof? Look at the recent temps in DC and Philly. Near or above 70! Geographically speaking, those two cities are not that far from us but those temperatures are quite warmer than anything we will see for a while. The warm air is making its push.

As for forecasting the rest of winter, your guess is probably as good as mine. One thing we must look at is recent climate. For 6+ weeks, we were in the line of fire of significant winter storms. These storms have not stopped being produced, we have just been shielded from them. I have to think that this will change.

Therefor, I DO expect one more snow storm for our area at some point between next week and mid March. It is very likely that the storm will not be all snow for everyone. Coastal areas usually get mixed or rain in these late season storms. But inland areas can get some heavy wet snow. Again, I have no actual proof of this happening, I am just using my weather logic to make and educated guess!

And besides, you couldn't think that mother nature could just drop 70 inches of snow in 1 month and then leave us high and dry for the rest of winter, do you?

Fun With Graphics!!

Today is cold

Starting tomorrow it will get warm!

Thursday and Friday will be even warmer!!!

Then it gets cold again. Haha. Welcome to the roller coaster!

Up and Down Week Ahead

So the good news is that we are entering our second week in a row of quiet weather. And a warm up is on the way! Although it is looking much more conservative than previously thought. But our snow pack will continue to melt and smiles will being returning to faces. And, we continue to gain 2-3 min of sunlight per day!!

Some highlights

- Warmest day will be Friday, where we should all be in the 50's. That will feel like 70 to our bodies.

- Coldest day will be on Tuesday when we get another, albeit brief, shot of arctic air. Tuesday night into Wednesday will be cold! But temps moderate each day from there

- I thought next weekend was going to be quite warm, with 60 degrees likely on Saturday but that is not the case anymore. We should still be warmer than normal but n0 60's

- Both jet streams continue to stay separate at least through next week. That means storms keep missing us to the north and to the south and we stay dry!

Greg Rambles

Some thoughts on this cold Wednesday in February.

- Greg officially hates Differential Equations. This is going to be a long semester that requires lots of hard work and patience, two things I generally lack.

- Man it got cold last night! Most of Eastern MA started the day in the mid 30's. By 4pm, we were in the upper teens! Arctic cold fronts get you every time. The wind was quite strong too. Think of it like this, if you have ever opened a sealed container and felt and heard air rush into it, that is what we experienced last night. Cold air literally rushing into our region.

- Potholes suck. Big time. And you all know that there are TONS of them out there right now. I hit one yesterday and it took me out. Some of them are ridiculously big. But honestly there is nothing you can do about them. You really can't fix them until we start getting consistently warmer weather , which is late March early April. Fix them now and they will likely open up again in a few days. Yuck!!!

- Feel free to wave goodbye to our near miss of a storm tomorrow. Currently it is wreaking havoc in the south. Areas like Arkansas, Alabama and Tennessee are getting a pretty substantial snow storm. Oklahoma City and Dallas saw significant snowfall for the second time in 1 week. Unusual for them and believe me when I say that these people have no idea how to handle snow. My friend Sarah Brown reports that Memphis has 5 inches of snow and there are accidents everywhere. Don't feel too bad for them though. These same areas will be close to 70 degrees next week.

- While we are on the topic of other places getting snow, Japan is getting a pretty good snowstorm as we speak. Something tells me that they are more efficient at cleaning it up though.

- I was not alive in 1969(in case you were wondering) but on Feb 8-9th, our region was currently getting leveled with what is famously known in New York as Mayor Lindsay's Snowstorm in. Although only 15 inches fell in the city, amazingly 14 people died! I know that forecasting has gotten better since then but judging by Bloomberg's reaction to this past December's snowstorm, New York still hasn't figured out how to deal with snow.

- My cousins better be reading this because I am using this space to talk about San Fransisco weather. And you know what the weather is? Boring. You guys are protected out there right now by strong high pressure. No rain in sight. In fact, that dryness might become a problem down the road. But for now, you will see sun and fun. Maybe not so much fun for the cousin who is pregnant with twins though.

- I intended to work on homework all night. Time spent on homework, 90 min. Time spent blogging and jerking around on the internet, well over 2 hours.

I think I will finish on that note. Stay warm!

Tomorrow? No Sweat

So for the first time in a long time this winter, two storms will be forming along the east coast and neither one is going to hit us.

Tonight, a storm will hit the water off the coast of North Carolina and slide harmlessly out to sea, several hundred miles south of Nantucket. At the same time, a weak storm will be moving towards us from the Great Lakes. This storm will be little more than a nuisance though but because that big storm will be providing some strong winds from the south to help enhance the little storm. Probably about 2-3 inches over interior MA and maybe 1 inch inside of I95 since surface temps will be close to if not above 32. This will all be over by mid afternoon tomorrow.

Many of you have asked about our MEGA storm on Thursday. Well its off, for us at least. A major pattern change is going to happen (although we might not see much of a difference in New England) and there is going to be some very cold air settling across much of the country, followed by a HUGE warm up. Remember how Dallas had snow and 20 degree temps this week? How about 80 degrees for them next week. Chicago might make it to the mid 50's. DC and Baltimore will get close to 60. This is all next week of course and before that, many of these areas will see a very large storm. Such temperature extremes always create big storms. This will be a big one for the deep south with snow/freezing rain and and ice. A big mess for them coming Thursday.

For us, we are now under the protection of a big High Pressure block. Its a good news/bad news situation. The good news is that this blocking high will push all storms out to sea and away from us. The bad news is that it will also keep us in a "cold bubble" that prevents us from seeing the big warm up that the rest of country sees.

Oh well.

Ladies and Gentlemen, The End is Near

So I apologize for my absence over the last few days. A combination of work, drinking and laziness generally are the reasons behind my lack of blogging. I have been getting some great feedback from people though and I love it so keep it up!

Some of that feedback centered around my post about a monster storm that was going to occur next Thursday. I have to admit that I was fueling the flames a bit on that one. Anything that is predicted 7 days out has a minimal chance of playing out the way it is predicted, however, I did have some basis for thinking this storm was and quite possibly still could happen.

Lets start with a quick explanation as to what has been going on this year. As most of you know, this year is classified as a La Nina winter. Simply put, La Nina is defined as cooler than normal sea-surface temperatures in the central and eastern tropical Pacific ocean that impact global weather patterns.Below is an image of what a typical La Nina winter pattern looks like in the US.

A few things to note. Notice that the northern portion of the jet stream typically stays to our north and keeps the real arctic air away from our region and also keeping us in a milder and wetter pattern. Also notice the strong moisture flow from the pacific into the pacific northwest, a pattern that was verifying early in December if you can remember how much rain and snow Washington and Oregon were getting.

Now lets take a look at what has happened since around Christmas time.

See the difference? The northern branch of the jet stream has shifted further south and at times has "phased" with the southern jet stream to tap into warm gulf moisture and create large winter storms that have continued to hit us over and over again. Another big difference is the cold air. Cold air has essentially been locked in over our heads for the last 40 days. This is one of the big reasons as to why we have had no melting and have large snow piles all over the place.

Obviously, this is a very quick rundown of our winter pattern this year and there are much more integrate things going on here that are playing into our very snowy 2011. However, I bring this point up to illustrate a bigger point. The end is near.

All signs point to a very large pattern change beginning next week and lasting quite possibly for the remainder of the winter. No image to show this right now but here are the 3 major points.

1. Storms will come from the West now instead of the south.
2. The south storms will move west of the coast providing bigger snows for inland areas.
3. The cold air is losing the battle with the warm air.

But of course, before this happens, we need a large storm to signal the shift in patterns. That storm still looks to happen on Thursday. Now, just because the storm will exist does not mean that it will hit us or even if it hits us, it does not mean that it will be all snow.

One thing is certain though. Expect warmer temperatures for the rest of the month starting next weekend. Let the melting and the march towards spring commence!

Want To See Something Scary?

Possible storm of the decade next Thursday?? Haha, I couldn't resist. But it looks big now, causing some buzz...

Impressive Storm Totals Nationwide

Here is the official NWS summary of our now departed storm.

Storm Totals

The Mid West got slammed with this one more than we did.

-Chicago had 19.5 inches of snow, 3rd biggest single storm total all time.

-Area in Wisconsin, Illinois, Missouri, Oklahoma and Vermont got over 20 inches of snow.

-Top wind gusts reached 78 mph in Tennessee! A sure sign that the storm was getting very intense

Why We Mix

So it should seem surprising to most people that in Boston last night around midnight, the temperature was 22 degrees. Even as I write this at 8:30 AM, my outside temperature in West Roxbury is 30 degrees, but I am getting all sleet right now. So how and why does this happen?

This reminds me of an argument I once had with my good friend Ryan Hansen. Hansen claimed that it HAD to be 32 degrees to snow no matter what. If it was any warmer, snow just couldn't exist. I, of course, disagreed and tried to explain to Hansen that it in fact can snow if the ground temperature is above 32. This is usually when you see those big almost fake looking snowflakes with very high water content. It is the result of cold air sitting right over our heads and precipitation falling very fast, so fast that it doesn't have time to melt before it reaches ground level. Of course, this snow doesn't stick to much of anything except grass and cars BUT it does prove that it can snow when it is above 32 degrees.

I bring up this story because sleet/ice and that magenta coloring that you see on your radars today works in a very similar way, just backwards. (On a side note, I love how mixing is depicted on the radar! Its like a ball of uncertainty coming towards you!!) Anyways, despite us having very cold air in place at the surface, you need to remember that our atmosphere is quite complex and more importantly, it continues up in the air for many miles! As I explained to Hansen, just because our surface temperature is cold enough for snow does not mean that we will get snow. The reason is somewhat complex, but in layman's terms, its because the air about 2000ft above us is too warm and is in fact above freezing.

This particular storm affecting us today is VERY large. Many people saw the satellite images of it yesterday and heard horror stories from the midwest of epic snowfall totals. This storm is so large that it began to suck up some very warm air from the Gulf of Mexico. That warm air ran into our firmly entrenched cold air (cold air that has been pretty much the result of a stationary high pressure system over Iceland all winter!). Our cold air actually won the battle, but as we all know, warm air rises and despite losing the battle at ground level, the warm air has risen above the cold air and now has the "high ground" which any battlefield nerd will tell you is the most important thing in a fight!

The result of this process is what you see today, sleet and ice. The air above us warms falling precipitation so much that by the time it hits the cold air at the surface, it doesn't have time to freeze back up. The result is sleet, which is basically just a half assed snow flake. Ice is much more dangerous. Ice happens when the falling precipitation makes it all the way down to the surface as just a cold rain drop but then freezes immediately on impact. This usually happens when there is a bigger difference in surface temp and low level atmosphere temp. I don't think Boston will have a problem with ice today because our surface temp will continue to warm up but other areas away from the influence of the water might have an icing issue.

Ok, so now you know why it sleets and ices. By the way, despite my logical explanation to Hansen, he still didn't believe me. Anyone who has ever had an argument with Hansen knows that he doesn't give up easily.

First Storm is Winding Down

Well, that was round 1. Rough timing with this one. I was witness to numerous spinouts and even minor car accidents. Not much you can do when you get heavy snowfall in the middle of the day. Generally 5-9 inches fell, which is what was forecasted.

Take a look at this. It gives you a very good image of our 1, 2 punch. That big guy in the middle is round 2.

She is a big storm, with lots of moisture to drop. She is also going to take a very strange path,which is the reason we have a lot of precipitation type questions.

Anyways, enjoy the break for now!