Please note that the following summary was written for the Pennsylvania State Climate Office. Give credit to the Climate Office's "The Pennsylvania Observer" publication.
In Punxsutawney, Pa, the world's most famous groundhog, Punxsutawney Phil, spotted his shadow on February 2nd which is supposed to translate to six more weeks of winter. With the weather Pennsylvanians experienced at the beginning of the month, this long range forecast seemed mighty believable.
Much of the eastern part of the Commonwealth saw significant snow accumulation on February 3rd through the 4th as the first Nor' Easter of the year slid up the coast. Stations in the southeastern Pennsylvania region reported snowfall totals averaging from 4” to 6” (10-15cm) with isolated bands of snow totaling 8” to 10” (20-25cm). After the system moved out of the region, cold air from Canada moved into the Commonwealth on February 5th and 6th pushing lows down to the negative digits in some parts. Bradford Regional Airport (KBFD) recorded a low temperature of -11F/-24C during the evening hours of February 5th.
Things drastically changed by the weekend of February 7th as warmer air moved into the region preceding the next low pressure system. The warming trend continued through February 11th with temperatures reaching highs in the low 50s (10-12C) to upper 60s (near 20C) across much of the Commonwealth. Philadelphia International Airport (KPHL) reported a high temperature of 69F/21C on February 11th. New record highs were set for Williamsport, Harrisburg, Allentown, Reading, and Philadelphia on both the 11th and 12th.
Temperatures remained above freezing while the low moved through Pennsylvania during the nighttime hours of the 11th and 12th. Although snow and ice were not a problem, winds ravaged the Commonwealth. The Storm Prediction Center’s records showed twenty severe weather reports of wind damage from just the western part of Pennsylvania. The average gusting winds associated with the system ranged from 50 to 60mph (20-25m/s).
Pleasant conditions developed across the Commonwealth making for an enjoyable Valentine’s Day and President’s Day weekend. This pattern changed on the 18th and 19th as a low-pressure system trekked northeast along the Appalachian Mountains bringing light to moderate snow showers to Pennsylvania. Much of the Commonwealth received 0.5 to 5 inches (1-12cm) of snow with the liquid equivalent ranging from 0.1 to 0.6 inches (3-18mm).
On George Washington’s birthday, February 22nd, a clipper system passed through the region bringing snow to the western half of the Commonwealth. After a minor cool down from the 23rd to the 25th, much of Pennsylvania saw a return to above-average temperatures.
For the month of February, the Commonwealth had maximum and minimum temperatures that did not depart much from the mean (most sections were within 1F/0.4C of normal). However, precipitation was a different story.
Much of the region measured below normal precipitation. Harrisburg was 2.33 inches below the average for the month. The National Weather Service Cooperative Observer site located at Chalk Hill in Fayette County recorded the maximum total precipitation of 3.52 inches for the month of February. The maximum total snowfall recorded was 34 inches in Laurel Summit, Somerset County.
Tuesday, March 3, 2009
Thursday, January 29, 2009
Nor'easter Anyone???
Could this be our first Nor'easter of the season? I feel it is pretty safe to say that we will see a nor'easter Monday night into Tuesday for this coming week, but there is one big question. Who is getting the snow and how much will they get? This may seem like a classic question, but the models have sent this storm all over the maps. I hope that by Sunday night some of my concerns are addressed by the model runs. Plan for an in depth discussion and possibly the weather blog's first podcast sometime this weekend.
Monday, January 26, 2009
Messy Winter Storm Coming!
Good evening everyone. We have a very interesting weather situation unfolding during the course of the day tomorrow through Wednesday for the State College area (and rest of Northeast). And of course, this winter storm system will not be clear-cut at all (just like every other one this season). Yet again, Central PA will not see JUST snow with this event as a change to sleet/frz rn for some portions of the area seems likely. So, let's take a look at what is currently going on:
Above is the current surface weather map for the US (courtesy of the HPC division of NOAA). We have a nice dome of 1036mb High pressure moving over the plains currently. This will move through the northern part of the country tonight and tomorrow bringing fresh cold air with it. To the south, in 4 corners region, lies the storm that will move NE tomorrow and bring snow with it.
The problem with the forecast (as always) is how much warm air gets brought into the upper levels of the atmosphere. We will have fresh cold air at the surface but the High pressure system will be moving out into the Atlantic during the day on Wednesday. This is not a great set-up for a major snowstorm. However, there is still a lot of potential here and certainly the possibility of a satisfying storm for the State College area.
The models have finally trended together and are close on a solution. They are not in total agreement but they are a whole lot closer than a day or 2 days ago. We'll take a look at the GFS, NAM/WRF, and the CMC (using the 12z runs for continuity...and the fact that the 18z runs are not the greatest).
12z GFS (for KUNV): Moderate snow develops after midnight on Tuesday night as the LOW moves through TN. Thicknesses are 539 dm which is barely cold enough to support snow BUT the 850 mb temps are nicely below freezing at -4.9 degrees C. As the snow intensifies toward daybreak on Wednesday, warm air is making an intrusion in the upper levels and thicknesses go up to 540 dm which is right on the border for snow (850 mb temps are borderline but still below freezing). The LOW is now over Norther VA and exits over Cape May during the afternoon on Wed. We get about .7o inches of QPF from this run which would be just over 7" of snow if it remained all snow. What concerns me is the placement of the 850 mb LOW. It goes over Northwestern PA and you don't want to be on the S side of the 850 mb LOW if you want to get the best snows. This tells me that the GFS says we will go over to sleet for a bit even though thicknesses remain marginal. Verbatim, the GFS gives us 4-8" (probably more on the 4/5" range with sleet mixing in).
12z NAM/WRF (for KUNV): The NAM is a bit slower than the GFS and brings precip in around daybreak (or a bit before) on Wednesday. The overall idea of the NAM is very similar to the GFS except the LOW tracks a bit further North which ends up giving us a little more warm air to deal with. Thicknesses climb to 541 at one point during the storm and the NAM even shows the surface warming to 32.1 degrees F. I find this hard to believe giving the good cold air damming situation and the fresh cold air we will be getting tomorrow. I'm confident that we will never get above freezing at the surface. Basically, the NAM wants to through a mostly sleet storm at us with about 1-3" of snow on the front end. As usual, the NAM is wetter with .90 inches of QPF. I think this is a bit overdone (although we do have a nice SW flow).
12z CMC (for KUNV): The CMC is the furthest north of the 3 models and tracks the LOW through KY, WV, over Allentown PA, and over Boston. As such, we REALLY warm the mid-levels of the atmosphere and go to sleet and most likely freezing rain for a lot of the storm. Storm QPF totals look about the same as the GFS.
My thinking: I'm going to go with a blend of the GFS and NAM and lean a bit more toward the GFS at this point. I think the NAM is too overdone with the QPF (it usually is) and I also think it gets rid of the cold air too quickly (also another bias of the model). The GFS to me has been the most consistent all along for this storm and in addition, the SREF ensemble mean leans toward the GFS as well.
Bottom line: Snow will develop around or a bit after midnight on Tuesday night and continue until about mid afternoon on Wednesday. We will definitely start off as all snow and probably pick up a quick 2-4" inches before any change over occurs. I DO think KUNV will go to sleet for a time and cut down on accumulations. I hope I'm wrong but it's hard for me to buy into all snow with the track of the 850 mb low. Around daybreak I think KUNV changes to a mix of snow and sleet and we pick up about 1-3" of that mess. And as the system moves out maybe and inch or two of snow. So, in the end, my call is for 4-7" of snow/sleet accumulation in State College. Best guess amount is 5".
Have a good night!
PS For those in the NYC area. I think NW of I-287 will see about 3-6". Far NW NJ and the Poconos will see 4-8" (local 10" in the Poconos). And NYC itself will see about 2-4" (mostly at the beginning of the storm).
Above is the current surface weather map for the US (courtesy of the HPC division of NOAA). We have a nice dome of 1036mb High pressure moving over the plains currently. This will move through the northern part of the country tonight and tomorrow bringing fresh cold air with it. To the south, in 4 corners region, lies the storm that will move NE tomorrow and bring snow with it.The problem with the forecast (as always) is how much warm air gets brought into the upper levels of the atmosphere. We will have fresh cold air at the surface but the High pressure system will be moving out into the Atlantic during the day on Wednesday. This is not a great set-up for a major snowstorm. However, there is still a lot of potential here and certainly the possibility of a satisfying storm for the State College area.
The models have finally trended together and are close on a solution. They are not in total agreement but they are a whole lot closer than a day or 2 days ago. We'll take a look at the GFS, NAM/WRF, and the CMC (using the 12z runs for continuity...and the fact that the 18z runs are not the greatest).
12z GFS (for KUNV): Moderate snow develops after midnight on Tuesday night as the LOW moves through TN. Thicknesses are 539 dm which is barely cold enough to support snow BUT the 850 mb temps are nicely below freezing at -4.9 degrees C. As the snow intensifies toward daybreak on Wednesday, warm air is making an intrusion in the upper levels and thicknesses go up to 540 dm which is right on the border for snow (850 mb temps are borderline but still below freezing). The LOW is now over Norther VA and exits over Cape May during the afternoon on Wed. We get about .7o inches of QPF from this run which would be just over 7" of snow if it remained all snow. What concerns me is the placement of the 850 mb LOW. It goes over Northwestern PA and you don't want to be on the S side of the 850 mb LOW if you want to get the best snows. This tells me that the GFS says we will go over to sleet for a bit even though thicknesses remain marginal. Verbatim, the GFS gives us 4-8" (probably more on the 4/5" range with sleet mixing in).
850mb Heights 48 HR Forecast (HPC/NOAA)
12z NAM/WRF (for KUNV): The NAM is a bit slower than the GFS and brings precip in around daybreak (or a bit before) on Wednesday. The overall idea of the NAM is very similar to the GFS except the LOW tracks a bit further North which ends up giving us a little more warm air to deal with. Thicknesses climb to 541 at one point during the storm and the NAM even shows the surface warming to 32.1 degrees F. I find this hard to believe giving the good cold air damming situation and the fresh cold air we will be getting tomorrow. I'm confident that we will never get above freezing at the surface. Basically, the NAM wants to through a mostly sleet storm at us with about 1-3" of snow on the front end. As usual, the NAM is wetter with .90 inches of QPF. I think this is a bit overdone (although we do have a nice SW flow).6 Hr Precip/850mb Temps 54hr Prog NAM (HPC/NOAA)
12z CMC (for KUNV): The CMC is the furthest north of the 3 models and tracks the LOW through KY, WV, over Allentown PA, and over Boston. As such, we REALLY warm the mid-levels of the atmosphere and go to sleet and most likely freezing rain for a lot of the storm. Storm QPF totals look about the same as the GFS.
My thinking: I'm going to go with a blend of the GFS and NAM and lean a bit more toward the GFS at this point. I think the NAM is too overdone with the QPF (it usually is) and I also think it gets rid of the cold air too quickly (also another bias of the model). The GFS to me has been the most consistent all along for this storm and in addition, the SREF ensemble mean leans toward the GFS as well.
Bottom line: Snow will develop around or a bit after midnight on Tuesday night and continue until about mid afternoon on Wednesday. We will definitely start off as all snow and probably pick up a quick 2-4" inches before any change over occurs. I DO think KUNV will go to sleet for a time and cut down on accumulations. I hope I'm wrong but it's hard for me to buy into all snow with the track of the 850 mb low. Around daybreak I think KUNV changes to a mix of snow and sleet and we pick up about 1-3" of that mess. And as the system moves out maybe and inch or two of snow. So, in the end, my call is for 4-7" of snow/sleet accumulation in State College. Best guess amount is 5".
Have a good night!
PS For those in the NYC area. I think NW of I-287 will see about 3-6". Far NW NJ and the Poconos will see 4-8" (local 10" in the Poconos). And NYC itself will see about 2-4" (mostly at the beginning of the storm).
Thursday, January 8, 2009
Winter Storm on the Way!
I hope everyone had a great holiday season and New Year! I know I did! I had the opportunity to travel to Pasadena, CA and the Rose Bowl with the Penn State Blue Band. It was an awesome experience. Now on to the weather.
We have certainly had our share of sleet storms and wintry mix in State College this winter. We seem to have trouble getting a good 4-8" all snow event. Each time we have moisture coming our way, the LO has come to close to the area and we end up with warm air intruding in the upper levels while Cold Air Damming (CAD) in our area remains strong at the surface. Result: SLEET. Well, this drought may be about to end on Friday night and Saturday!
Currently, we have a nice dome of cold air (-10 degrees C at 850mb) moving over our area. We will then see the southern and northern jet streams partially phase and create a nice area of LO pressure over the Southern Ohio Valley on late Friday. The LO will move East through VA on Saturday and off the DE and NJ coast by early Sunday morning. There is fairly good agreement among the models at the current time with the latest (0z) NAM coming into line with the 12z and 18z GFS runs. Below is the 54 hr NAM from the 0z suite:
At this point, it looks like the cold air will hold strong and the track of the LO will be far enough south for KUNV to remain all snow. The 850mb LO is a little to close for comfort but soundings show all snow at this point.
Overall, I am extremely confident about this storm system being a good snow event for a line 50 miles either side of I-80 through PA and NJ. As an early call, I'm going to forecast 3-6" for that area with localized amounts in the 6-8" range. The NAM usually overdoes precip and I don't like it's ~.75 QPF. Yes this system has southern stream moisture with it, but I can't see that much liquid. I like the GFS's QPF output a lot better. .5 inches and a little greater seems much more reasonable.
I hope the 0z run of the GFS doesn't through a curveball into the equation. The only outlier is the Euro which is usually better in longer range situations anyway. So, for now, I like my early forecast and think KUNV will remain all snow (the NWS even had a Winter Storm Watch out early this afternoon). Precip should end at state college before midnight on Saturday night.
Have a good one everyone!
We have certainly had our share of sleet storms and wintry mix in State College this winter. We seem to have trouble getting a good 4-8" all snow event. Each time we have moisture coming our way, the LO has come to close to the area and we end up with warm air intruding in the upper levels while Cold Air Damming (CAD) in our area remains strong at the surface. Result: SLEET. Well, this drought may be about to end on Friday night and Saturday!
Currently, we have a nice dome of cold air (-10 degrees C at 850mb) moving over our area. We will then see the southern and northern jet streams partially phase and create a nice area of LO pressure over the Southern Ohio Valley on late Friday. The LO will move East through VA on Saturday and off the DE and NJ coast by early Sunday morning. There is fairly good agreement among the models at the current time with the latest (0z) NAM coming into line with the 12z and 18z GFS runs. Below is the 54 hr NAM from the 0z suite:
At this point, it looks like the cold air will hold strong and the track of the LO will be far enough south for KUNV to remain all snow. The 850mb LO is a little to close for comfort but soundings show all snow at this point.
Overall, I am extremely confident about this storm system being a good snow event for a line 50 miles either side of I-80 through PA and NJ. As an early call, I'm going to forecast 3-6" for that area with localized amounts in the 6-8" range. The NAM usually overdoes precip and I don't like it's ~.75 QPF. Yes this system has southern stream moisture with it, but I can't see that much liquid. I like the GFS's QPF output a lot better. .5 inches and a little greater seems much more reasonable.
I hope the 0z run of the GFS doesn't through a curveball into the equation. The only outlier is the Euro which is usually better in longer range situations anyway. So, for now, I like my early forecast and think KUNV will remain all snow (the NWS even had a Winter Storm Watch out early this afternoon). Precip should end at state college before midnight on Saturday night.
Have a good one everyone!
Friday, December 26, 2008
Hurricane Season 2008 Summary: Introduction
Finally, now that classes have ended, assignments are no longer due, and the Christmas rush has come and gone, ... It seems like it is time for me to begin my Atlantic Hurricane Season 2008 summary. Much like the National Hurricane Center's summary, my summary will contain information about each and every single storm of the season. However, I plan on interjecting my own opinions, comparisons to previous seasons, and other interesting facts throughout these posts. This summary will be divided up into several different "chapters" that I will post one at a time as I finish them. Some of the sources that I plan on utilizing are NOAA, wikipedia, and possibly some news outlets. I greatly encourage all of our readers to make their own comments on my summary because as much as I'd like to be, I am still not an expert in tropical meteorology. For now I will leave you with a tentative "table of contents" if you will. All the "parts" of the summary will hopefully be published on this site by the time the spring semester starts on January 12th. Until then, I wish everyone a belated Happy Holidays, and a Happy New Year!
EXPECTED "TABLE OF CONTENTS"
Part 1: Quiet Beginnings
-Look back at 2007, preseason expectations, and finally Arthur
Part 2: The Atlantic Warms
-From Bertha to Fay
Part 3: The Peak Months
-Hanna, and introductions to Gustav and Ike
Part 4: Major Hurricane Gustav
-detailed look at Gustav with a look back to Katrina from 2005
Part 5: Major Hurricane Ike
-detailed look at Ike with comparisons to the 1900 Galveston storm
Part 6: Season Finally Winding Down
-From Kyle to Paloma
Part 7: 2008 in Perspective
-conclusions, records, averages, etc, and a look towards 2009
EXPECTED "TABLE OF CONTENTS"
Part 1: Quiet Beginnings
-Look back at 2007, preseason expectations, and finally Arthur
Part 2: The Atlantic Warms
-From Bertha to Fay
Part 3: The Peak Months
-Hanna, and introductions to Gustav and Ike
Part 4: Major Hurricane Gustav
-detailed look at Gustav with a look back to Katrina from 2005
Part 5: Major Hurricane Ike
-detailed look at Ike with comparisons to the 1900 Galveston storm
Part 6: Season Finally Winding Down
-From Kyle to Paloma
Part 7: 2008 in Perspective
-conclusions, records, averages, etc, and a look towards 2009
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