These Snow Forecasts Never Get Easier

With all this heavyweight computing power and myriad observations this was the best we could do-vague and inconsistent guidance!

nws watches map.jpgThe weekend snow seems to be coming into sharper focus. I say “seems” because I won’t know for sure until the whole thing is gone. It’s been a wild, incredibly inconsistent ride which isn’t over yet.

Last night before going on-the-air I looked closely at the 00Z&#185 GFS and NAM models. The NAM called for a blizzard. The GFS had a windy day with light snow.

Before bed I took another look.

The 06Z runs were in. The NAM had gone from Armageddon to nothing! It was now showing the storm missing us! I sent a text message to Gil Simmons who was already preparing his forecast at work:

Geoff: Nam to 60h. Sorry snowman.

Gil: WTF. Gfs still had some measurable.

Gil: Nothing like flushing hrs of work

Gil: What a joke

He was right–What a joke. With all this heavyweight computing power and myriad observations this was the best we could do-vague and inconsistent guidance!

I went to bed.

I woke up this morning and checked my phone. Craig Allen, New York’s best known broadcast meteorologist, was on Facebook. He was complaining about the Weather Service’s freshly issued “Blizzard Watch” for Long Island. It was much too early considering the inconsistency of the forecast and the immense impact on the weekend before Christmas.

By experience on-air forecasters understand it’s easier to cancel an event than un-cancel it! There’s no harm in waiting a little while longer. On the other hand there’s plenty of downside committing to a watch too early.

Before starting this entry I took a look at the 12Z GFS and NAM. Major snow is back in the NAM. The GFS has become less of an outlier and is now closer to (but still less than) the NAM solution. These models and a few more will form the basis for my forecast today.

I will spend the next few hours mulling over each detail. How much wind? When will the snow start? Will there be a burst period? What about the critical cloud temperatures which will define the snow’s fluff factor.

In the end I’ll hope to be close. There’s no bullseye in snow forecasts. You’re never exactly right. You can only hope people are well prepared and critics cut you a little slack.

&#185 – To achieve global consistency all weather data is produced in “Z” time aka UTC or GMT. This time of year it’s five hours ahead of EST. So 00Z means 7:00 PM EST. That’s the initialization time. It takes a few hours for the results to trickle out.

Hurricane Bill–Wide Right!

The surf will be angry. The beaches will be empty of bathers.

bill-sse-cape-cod.jpg

Hurricane Bill is down to Category 1 at the moment. I can see that in the satellite shot. The eye has become ratty. Convection is missing from much of the western side. Most importantly, it looks like dry air is getting in toward the center.

LARGE SWELLS GENERATED BY BILL ARE STILL AFFECTING THE EAST COAST OF THE UNITED STATES. THESE SWELLS WILL CONTINUE TO SPREAD NORTHWARD INTO THE CANADIAN MARITIMES ON SUNDAY…CAUSING EXTREMELY DANGEROUS SURF AND LIFE-THREATENING RIP CURRENTS. – National Hurricane Center technical forecast discussion

Earlier tonight on Facebook Craig Allen posted some personal observations from Jones Beach on Long Island&#185 which was disappearing under the tidal surge.

Just got back from Jones. Not Jones Beach; Jones Ocean. THERE WAS NO BEACH! All the sand was COMPLETELY submerged under the ocean from West End to Field 6. The ocean continued under the boardwalk, splashing up from between the slats and flooded the g…olf course. Only the top 2 feet of the basketball hoops were visible. The bandshell was under 3 feet of water. Only the dunes prevented it from flooding the parkway. – Craig Allen, meteorologist

Without Long Island we’d be susceptible to all that Bill’s got. Of course that’s academic. Thanks for taking one for the team Long Island!

Offshore, NOAA’s buoys continue to see large swells even in areas without strong winds!

There will be plenty of video later today from Massachusetts. The surf will be angry. The beaches will be empty of bathers.

Close but no cigar for Bill. Connecticut gets a pass. He will be Canada’s problem now. We are happy to see him depart.

&#185 – Actually Jones Beach is south of Long Island on a barrier island called Jones Beach Island. This is one of those cases where what is true and what is commonly believed are at odds.