Ph.D. Student - Earth System Science (UC Irvine), B.Sc. - Atmospheric Sciences (Cornell University)
By: Zachary Labe , 9:56 PM GMT on September 26, 2009
"Afternoon Thoughts"(Updated 9/26)
Looking back at the past year in weather across the Northeast, I find it hard to pinpoint any storm of any significance. Not that this is a bad thing, as the relatively quiet in nationwide weather is probably better for the economy; but it is interesting how benign the weather pattern really has been. Yes there have been several extreme weather anomalies, for instance take the recent Atlanta metro flooding with up to 19inches of rain, but looking on a large-scale level it is hard to find much. Fortunately hurricane season 2009 was extremely quiet as expected with only some minor impacts to the United States coastline. Looking at the overall pattern, it appears most tropical activity is going to continue to quiet down so hopefully those along the coastline can continue to breath a sigh of relief. Even the winter of 2008-2009 featured hardly anything of record, perhaps just a short January arctic blast with a day of negative lows but again nothing of too much memory. Large-scale storms were hard to come by even causing the winter to be one of the driest on record for the Middle Atlantic. Then as we entered Spring, Vortex2 sent out there mission of tracking and researching tornadoes; but we have one of the quietest tornado seasons in recent memory this year. Then Summer comes along with well below normal temperatures for most of the country. Sure the Texans would not agree with that statement, but looking on a widespread level and not pin-pointing extreme weather anomalies, hot/hazy/humid weather was hard to come by. And then as earlier mentioned we enter hurricane season, which turns into the quietest in recent record. Now I suppose we are fortunate to have the lack of extreme weather, but it sure is interesting how quiet the pattern has been. I wonder when this will change? In any case I guess I cannot call the Lower Susquehanna Valley this year "where storms come to die," because the entire country has been lacking in storm activity. In any case as Joe Bastardi always says, "Enjoy the weather! It's the only weather you've got!"
(Courtesy of NOAA)
"Current Weather Map"
(Courtesy of Wunderground)
"7-Day Forecast Discussion"(Pennsylvania, Maryland, Delaware)(Updated 9/26)
Relatively high confidence forecast this week looks likely with a bit of active weather earlier in the week transitioning to cool and dry weather later in the week. 1000mb low pressure will be moving up through the Ohio Valley across the Northern Middle Atlantic overnight Saturday into Monday. A moderate 35knot low level jet and isentropic lift will allow plentiful moisture to development streaming northeast from the Gulf of Mexico. PWATs will rise to near 1.75inches which is 1-2STD deviations above normal. GFS in particular shows a period of moderate to heavy Saturday night across the entire region, but especially southern Pennsylvania through Maryland and Delaware. At times Saturday night rainfall rates will approach .5inches per hour as the low level jet strengthens. Water vapor loops and current visible satellite already show a large expanse of clouds and moisture aloft with a dense stratiform stratus cloud deck dropping conditions to IFR conditions Saturday with ceilings as low as 300ft. Moderate low level shear will also promote some breezy conditions Saturday out of the south-southwest near 15mph. With low stratus and widespread rain with RH values near 100%, low temperatures Saturday night will not drop too much from dewpoint values in the mid to upper 50s with low 60s for Washington DC. Rainfall will continue much of the night as the low progresses east-northeast out towards the Atlantic Sunday morning. Rainfall totals will be moderate soaking rainfall with 1-2inch totals over the entire Middle Atlantic. The heaviest rainfall totals will likely be over western Maryland and the southern Laurel Highlands where orographic lift will enhance rainfall rates overnight. A few timing discrepancies arise between the models for the end of the stratiform rain, but for most areas it appears the rain will be done by 12pm-1pm with scattered alto-stratus clouds through the rest of the day and occasional drizzle over northeastern Pennsylvania in the Poconos. Under a southwesterly flow ahead of a negatively tilted trough, highs will rise warmer than Saturday in the mid to upper 70s for areas in Maryland, Delaware, and southern Pennsylvania with highs in the low 70s along and north of interstate 80. H85s rise to near 13C and with a few peaks of sunshine, an 80degree high or two cannot be ruled out especially for the major metropolitan region. Inversion should maintain low ceilings over the mountains throughout the day as low as 500ft (MVFR conditions). Skies remain mostly cloudy through the evening into Sunday night as an advancing steep trough moves through the Ohio Valley. A few areas of clearing may develop, especially in the east to perhaps aid in fog development. A linear vertical change in humidity aloft though will be partial to stratus development and not fog, but a few areas of dense fog (.25mile visibility) cannot be ruled out overnight Sunday. With high RH values over 75% and mostly cloudy skies, lows will again not drop off too much generally into the low 60s for most of Delaware and Maryland with upper 50s for most of Pennsylvania and far western Maryland. Monday features an interesting day with our first true Autumn front. Crashing H85 heights below 10C accompanied by a steep trough and tight pressure gradient will allow for a strong cold frontal passage with gusty winds and possible rain showers. Veering wind profiles aloft and moderate low level shear with helicity values near 534 m2/s2 during Monday will cause the potential for an isolated strong wind gust over northern Pennsylvania. A strong upper level low, 984mb, advancing quickly through Quebec and Ontario will be the catalyst for the gusty winds. Looking at convective indices, CAPE values only rise to near 50 j/kg profiles for most of the region. Areas south of I-80, away from the better dynamics will escape with only rain showers and an isolated thunderstorm. A low-topped squall line is highly possible Monday morning from New York State south through extreme northern Pennsylvania. 0-6km shear values approach 60knots and any higher core thunderstorm that forms could mix down some gusts of 50mph to the surface especially towards the Great Lakes. QPF totals will only be near .25inches for most areas with only a frontal rain band. A weak thermodynamic field should inhibit most thunderstorm development under a moderate CIN environment. At this time I am not too concerned for the Middle Atlantic, with any squall line probably limited towards New England. Monday will generally featured rain showers immediately along the front with partly to mostly alto-cumulus clouds throughout the day. Highs will be in the low 70s for most all areas dropping steadily with a frontal passage for western Pennsylvania around 8am, 12pm for central Maryland and Pennsylvania, and after 3pm for the rest of the area. A 277degree cyclonic flow will presume after the frontal passage for Monday night with breezy conditions under the tight pressure gradient. Gusts above 1500ft will be near 35mph with gusts in the valleys near 25-30mph. Dewpoints will be on the fall also Monday along with temperatures with lows chilly near 39degrees for extreme northern Pennsylvania with lows in the 40s for most of central, northeastern, and western Pennsylvania. Lows for Maryland and Delaware will be slightly milder courtesy of the later frontal passage with lows in the 50s to near 60 for Baltimore and Washington DC.
Tuesday will feature a cyclonic northwest 314degree flow with a bit of lake effect precipitation for far northwestern Pennsylvania. Lake temperatures in the 70s with highs in the 50s up in that region will promote some scattered rain showers with QPF generally at or below .1inches. Much of Tuesday looks to remain typical of a northwest flow with widespread clouds over the mountains and some clearing to the east courtesy of downsloping. Highs will be near 10degrees below normal with H85s around +2C. Across central Maryland and all of Delaware highs will be in the mid to upper 60s including Washington DC. Across western Maryland up through western and central Pennsylvania highs will range from the upper 50s to low 60s. For northern Pennsylvania highs will be in the mid to upper 50s with a few low 50s possible across Potter and McKean Counties. Tuesday night will feature mostly cloudy skies over the region with a semi-relaxation of the gusty winds from 20mph down to 10mph. Lows will range in the 40s for most areas north of the Baltimore-Philadelphia corridor. Across areas south of that line lows in the 50s will be the common place. Wednesday will feature a reinforcing shot of cold air as a closed 500mb low moves through southern Canada with a weak-undefined cold front draped through the Northeast. This will allow for the coldest air of the season with H85s dropping at or below 0C through the Mason-Dixon Line. Highs Wednesday will be similar to Tuesday's highs in the 50s and 60s for all areas under partly to mostly cloudy skies. Once again a few lake effect rain showers will cause a few hundredths of an inch of rain in the northwestern parts of the state. But also a few rain showers could be across the rest of western and central Pennsylvania associated with the advancing shortwave. Wednesday night will feature an advancing eastward Anti-cyclone, which will allow for clearing skies for much of the Middle Atlantic. But up across northern New England, the Adirondacks, White Mountains, and Green Mountains will likely pick up the first snow of the year. Typically in late September and early October H85s must be around (-4)-(-6)C for snowflakes, and that looks possible towards the mountains with an upslope orographic lift event. Elevations above 4000ft may pick up a coating to inch of snow overnight, so for those in the region you may want to check out the peaks especially towards Mt. Mansfield early Thursday morning. Lows Wednesday night for the Middle Atlantic will range from the mid 30s over northern Pennsylvania to low 50s near Washington DC. The cold pool aloft centers itself over the region for Thursday with the associated high pressure, 1024mb. With H85s below 0C through most of the Middle Atlantic a few cold nights are certainly in store. Thursday will feature sunshine generally over the entire region with a few clouds over the higher elevations of western Maryland and Pennsylvania about 1700ft. With dewpoints in the 30s over the entire region, it will feel pretty chilly with highs in the mid 50s for northern Pennsylvania up to mid 60s for southern Maryland and southern Delaware. Thursday night will be the coldest night of the young season with dewpoints in the 30s with clear skies and calm winds ideal for radiational cooling. Lows will likely fall at or below freezing for the northern parts of Pennsylvania with patchy frost in the I-80 corridor. Lows in the upper 30s to low 40s are expected elsewhere. I would not be surprised though if these low numbers get colder with frosts as far south as the Pennsylvania turnpike and northern Maryland near Garret County. After some patchy morning fog and frost Friday morning, sunshine will prevail through the afternoon with once again well below normal temperatures. Highs will be in the upper 50s to upper 60s throughout the region. Once again ideal radiational cooling conditions for Friday night, but a few clouds, cirrus, may try to work in late overnight. Still frosts are possible on a widespread level with lows ranging from 30-45 over the Middle Atlantic.
(Courtesy of Wunderground)
(Courtesy of Penn State Meteo.)
"Lower Susquehanna Valley Forecast"(Franklin, Adams, York, Lancaster, Cumberland, Perry, Dauphin, Lebanon Counties)(Updated 9/26)
Well below normal temperature week is in store for the Lower Susquehanna Valley along with a decent soaking rain. Increasing moisture from the Gulf of Mexico associated with a low pressure system moving across northern Virginia will allow for a period of moderate to heavy rain Saturday night. Increasing boundary layer southeast winds will allow moisture to pile up along the southern facing ridges causing low clouds with ceilings as low as 300ft and patchy fog, visibilities around 3-5miles. Also some stronger winds aloft may cause it to be a bit breezy during the rain making it feel quite chilly outside Saturday night through early Sunday morning. Lows Saturday night will be similar to dewpoint values in the mid to upper 50s over the valley with a few colder numbers for elevations above 1000ft in northern Dauphin and Lebanon Counties along with Franklin and Adams Counties. Rainfall amounts will be a widespread 1-2inches over the region with highest totals along South Mountain courtesy of the favored upslope enhancement. Rain should be ending by early Sunday morning as the low pulls off to the northeast across Long Island on off the coast. Under a more southwest flow Sunday conditions will try to improve, but with an inversion stratus clouds may be hard to budge especially during the first half of the day. With slightly rising temperatures aloft, highs will be several degrees warmer than Saturday rounding out in the upper 70s near York and Lancaster to mid 70s from the Pennsylvania turnpike corridor on northward. Mostly cloudy skies will prevail most of the day with patchy morning drizzle and fog. Any additional rainfall will be light and generally less than a tenth of an inch. Sunday night will feature partly cloudy skies over the region with a slightly southwest breeze ahead of a steep south-north facing trough advancing east from the Great Lakes. Coupled with a strong upper level low in Canada, the cold frontal passage will be the first to pose more Autumn characteristics. But overnight Sunday lows will be in the mid 50s throughout much of the Lower Susquehanna Valley, which is actually a tad above normal. Monday will be the cold front passage around noon with a chance of a low-topped rain shower squall line that may pull some of the gusty winds aloft to the surface. Best dynamics remain north of Harrisburg though in this instance. In any case the narrow precipitation frontal band should only cause a little bit of rain with amounts no more than .25inches. As the front moves through temperatures will slowly fall Monday with highs ranging from low 70s over Franklin, Cumberland, Adams, and Perry Counties to mid 70s over Lancaster and Lebanon counties. Breezy conditions will prevail by evening courtesy of cold air advection and the northwest flow. Monday night will be a bit breezy and partly cloudy with lows ranging from upper 40s in northern Perry, Dauphin, and Lebanon Counties to low 50s for Lancaster County. Winds should not exceed 25-30mph for the most part. Tuesday will feature a typical northwest flow with partly cloudy skies over the eastern parts of the Lower Susquehanna Valley courtesy of downsloping, but clouds over the western half especially in Franklin County. Highs will slowly rise throughout the day and struggle to reach the 60degree mark for elevations above 900ft. The cities of Harrisburg, York, and Lancaster will see highs in the low to mid 60s. Tuesday night the winds will finally begin to settle and skies will slowly clear ahead of another advancing shortwave. Lows will be in the mid to upper 40s over the region with dewpoints in the low 40s or perhaps upper 30s over northern and western Perry County.
Wednesday features the cold pool aloft centering over the Northeast as another shortwave in Canada accompanies a weak undefined cold front that will move through during the day. H85s heights will drop below 0C causing the coldest conditions of the season. Partly to mostly cloudy skies will occur Wednesday over the Lower Susquehanna Valley with a chance of a few spotty rain showers. Precipitation totals generally though will remain at or below a tenth of an inch. Highs will be in the upper 50s to low 60s over the region. Wednesday night conditions begin to clear out for a cold night as winds decouple towards the pre-dawn hours of Thursday allowing lows to dip into the low 40s for the northern half of the valley with mid 40s for areas in Lancaster and York County. Mostly sunny skies will prevail Thursday after some patchy morning river fog that will form near the Clarks Ferry Bridge courtesy of the extreme water/air temperature contrast. Thursday will be a beautiful Fall day with highs in the low to mid 60s over the region with brilliant sunshine. Dewpoints will drop into the 30s by evening as winds will relax as high pressure approaches from the west. Thursday night will feature the coldest conditions so far with lows possibly into the mid to upper 30s especially north of the Pennsylvania turnpike. Depending on dewpoints, frost may be possible for some areas, but I will have updates throughout the week as the threat becomes closer. Friday again features a beautiful day with well below normal temperatures continued under brilliant sunny skies after patchy morning frost and radiation fog. Friday night will feature clear skies for the first half of the night with increasing stratus overnight ahead of the next shortwave/front combo for Saturday. Lows will be very cold Friday with even some guidance printing out lows in the low 30s. Again I will focus in more on this threat later in the week.
"Current Lower Susquehanna Valley Radar"
(Courtesy of Wunderground)
"Chesapeake Bay and Atlantic Coast Marine and Boating Forecast"(Maryland and Delaware Coastal Forecast)(Updated 9/26)
It does not look like the best week for marine interests with several days of small craft advisory thresholds. A low pressure will move across northern Virginia and out to sea through Sunday afternoon. Low level wind shear will allow breezy winds to mix down to the surface with gusts over the Chesapeake Bay near 25knots through Sunday evening. Heavy rain will also occur with QPF totals near 1-1.5inches. Conditions will remain very poor through Sunday evening. Areas of advection fog may also form off the Atlantic coast a few nautical miles along with wave heights up to 6-8ft just offshore. Winds may approach 30-35knots along the Atlantic Ocean coastline through Sunday evening. Along the heightened waves and wind, the southeasterly flow will cause some coastal flooding as the southeast flow channels the water up the Chesapeake during high tide Saturday night through Sunday night. Prone splash-over areas may see tidal levels up to 2ft above normal. Monday another cold front approaches the region with a strong tightened pressure gradient causing an extension for small craft advisory conditions. An isolated thunderstorm is also possible along with spotty rain showers associated with the frontal passage. Winds will approach 30knots over the water Monday and this will last through Tuesday. The flow will turn more northwesterly allowing any coastal flooding to end by Monday morning. But wave heights and winds will remain in moderate levels for Fall standards through Tuesday evening. Another weak shortwave approaches the region Wednesday causing much colder conditions and breezy conditions again, but for now it looks like conditions remain below small craft advisory thresholds. Thursday and Friday, an anti-cyclone will allow for a relaxed pressure gradient with calmer seas and wind, but temperatures will be chilly with overnight lows in the 40s for coastal waterways. Water temperatures are just about now beginning their turn-around slowly cooling each week. By the weekend it appears a weak front approaches the Middle Atlantic, but nothing overly threatening looks likely.
"Current Atlantic Coast Forecast Wave Heights and Chesapeake Bay Forecast Wind Direction/Speed"
(Courtesy of NOAA)
"Updates on Winter Predictions" (Updated 9/26)
This section has been recently added this week and will last through the month of October is replacement of the Garden/Agriculture section. This section allows me to keep updating how the ENSO is evolving and the northern Pacific situation. Also we will be able to see how conditions are presenting themselves in contrast with my winter forecast. By the way this year I have decided not to issue an updated winter outlook forecast like I did in 2008. Anyways interesting conditions are occurring across the equatorial Pacific which will make this winter one for the analog books. We have a present El Nino with +.75-1C anomalies across the ENSO regions. But what makes this +ENSO interesting are the indices completely promoting a contrasting appearance. For nearly the month of September the SOI readings have been negative more indicative of a La Nina than El Nino, which proves very interesting. Also with unusual QBO, ONI, and GLAAM readings that seem to support Nina, it is surprising to watch each day. While yes there will be fluctuations from time to time and yes people are quickly overreacting, it is so interesting how the name La Nina keeps on coming back. If we look back at last winter and even the Summer 2009, La Nina unexpectedly dominated the global weather pattern regime. And even this Fall there are a few slightly noticeable lingering La Nina effects in the Pacific. Now I am not saying a La Nina is coming this winter, but I am just throwing some ideas on the plate. Also it is interesting to look at the latest ENSO regions with cooling SST positive anomalies in regions 1+2, 3; but regions 3.4 and 4 have remained relatively steadfast. This is a sign of the weak footing the El Nino has, but also a sign the El Nino is still approaching being west based and not basin wide which is in correspondence with the forecast. Finally I want to mention the PDO. This is my biggest concern this winter as there are some select signs already that there may be a blasting Pacific jet. A large cold pool in the Gulf of Alaska is showing up on SST anomaly charts which is indicative of a negative PDO. But a few positive anomalies on the southern edge of the pool gives me hope that the PDO will not be as negative as last winter. Now these thoughts above are only really thoughts at this point as winter is an "educated guessing game." But one thing for sure is this winter is not going to behave strictly like any analogs. I can see reason for people to fear a warm winter again, but for now I do not see any reason for alarm. In the end I suppose Mother Nature will do what she wants to do.
Winter Outlook 2009-2010...Link
"Equatorial Pacific SST Anomalies"
(Courtesy of NOAA)
"Average Date of First Freeze"
(Courtesy of NOAA)
"Fall Foliage Outlook" (Updated 9/26)
Ah next week is the start on one of my favorite months of the year, October. It is amazing that we are already almost a week into the official start of Fall and that some areas are seeing peak fall foliage. Looking first at Pennsylvania, northern Pennsylvania is seeing decent color courtesy of very chilly nights and a few frosts. Fall color in the maples is nearing peak in the week or two for elevations above 2200ft across Potter and Tioga Counties. Wildflowers are also in full bloom for northern Pennsylvania, but also region wide. Oaks are beginning to show some signs of yellows across northern Pennsylvania with invasive species and ornamental trees across northern Pennsylvania at or past peak. Brilliant oranges and reds will be likely by next weekend near the Pennsylvania Grand Canyon outside of Wellsboro. For those who have never ventured up that way, it is well worth the trip. Towards the central third of Pennsylvania including the Laurel Highlands, Ridge and Valley region, and the southern Poconos aspens are beginning to turn yellow along with birch across the coal country. Suburbia maples have turned red or showing signs, but mountains generally remain patchy with only some lighter greens, browns, or light yellows appearing in the Ridge and Valley Region. For the Laurel Highlands colors are decent with maples and even oaks beginning to show color. Peak fall foliage will likely be by the end of the first full week in October. The mountains of the Poconos are also showing color, but still have a bit before peak. Across the southern Pennsylvania color is a bit more spotty than the northern neighbors, but colors are still a few days to a week or two earlier than normal. Colors are now slightly evident showing on higher ridges, especially towards the western facing side of South Mountain. Peak fall foliage is looking likely for this region by mid October. For the Philadelphia region through Delaware and central/southern Maryland fall colors are very spotty, but now a bit more color is showing than just distressed and diseased trees. Sumac and other invasive species are turning red and ornamental trees are showing signs of color change. Maples are beginning to show small signs of reds and oranges, but oaks have quite a bit in this region before color change with peak fall foliage likely around late October this year. Finally western Maryland around the Garret County region or so is showing brilliant fall colors for the higher elevations and the next two weeks look wonderful for a drive out to this region. Maples and even oaks are showing through the mountain sides and farm country. Overall this week will allow for more evident color change by next weekend with very chilly nights and below normal temperatures all week. Also Thursday and Friday with the cold nights and sunny days will allow for the chlorophyll to break down in the leaves. Happy Fall!!!
Fall Foliage Reports... Link
"Long Term Outlook" (7-14 Day Time Frame) (Updated 9/26)
Towards next weekend it looks to be generally under a similar theme with below normal temperatures and possibly a weak front passing through the area Saturday, although I do not think it will be too much of a problem for the weekend. It is hard to believe next weekend is the first full weekend of October! Anyways I think the pattern is looking for interesting for the next two weeks. In October we start to see signs of patterns that may hold through the first half of winter. What makes the next two weeks interesting is the impressive west-based negative NAO which will reach its height during the first few days of October and slowly retreat back to neutral overtime. Also impressive above normal 500mb hPa heights are going to be located over the Hudson Bay and western Greenland forming a strong blocking pattern, which again will slowly relax by October 7-10. The pattern appears the first week or two of October is a series of troughs over the east coast with well below normal temperature anomalies and near normal precipitation. Towards mid October the pattern retrogrades as expected, remember my balance of equilibrium theory. With a trough then centered over the Rockies, we still enter a near normal to slightly below normal temperature pattern over the east coast as weak upper level lows rotate through the region courtesy of a negative EPO. As long as the NAO does not stay brutally negative most of the month, historical odds will favor a colder than normal winter as we will have a below normal temperature anomaly for the month. Overall I do not see any extreme warmth headed towards the Middle Atlantic anytime soon. A few bouts of warmer than normal temperatures are likely towards the second to third week in October as a trough forms over the west, but for now that looks temporary with GFS/GEFS means producing a positive PNA by mid month. Generally the pattern is reminiscent of typical slightly below normal temperature Octobers with a volatile pattern with occasional weak mid level ridges followed by quick weak troughs and associated upper level lows.
"Current NAO and PNA Predictions"
(Courtesy of NOAA)
"Monthly Temperature/Precipitation Outlook"(October)(Updated 9/13)
This monthly outlook is going to be posted a bit early this year for October. I never issued a September forecast and now it is the middle of the month so I decided to forecast October instead of the last two weeks in September. Therefore this outlook is a bit lower than normal for confidence. As many probably could guess I am going with a colder than normal October. Long term GFS especially is consistent with trough formation over the east coast and an amplified western ridge. Latest ECMWF is also steadfast, but not amplified with weaker western ridge and a weaker trough, but they are still evident. Teleconnections are a bit more favorable also for a cool pattern across the east coast. It appears the PNA will be spiking highly positive towards October 1 with the NAO and AO more towards neutral. As far as precipitation it appears near normal precipitation is likely with a drier start to the month gradually becoming more active. If the cooler than normal October verifies historical odds definitely favor a colder than normal with quite a bit of snow for the upcoming winter. I guess all we can wish for is not another October 2008 which was extremely mild and again followed by a mild winter. Looking on a more global perspective there is a building dome of cold air over the Arctic towards Greenland and northern Canada. This cold air will continue to build and likely be a catalyst for bits of cold air to break off and surge to the United States with strong cold fronts.
Temperature- As I already mentioned I believe this month will feature cooler than normal temperatures will a general trough over the Middle Atlantic. I think areas north of I-80 will have the colder anomalies as occasional stalled fronts affect southern Pennsylvania, Maryland and Delaware with clouds and precipitation while highs to the north allow radiational cooling for northern Pennsylvania. I am going with a general (-1)-(-2) temperature anomaly for most areas with a generally (0)-(-.5) for the metros of Philadelphia and Washington DC. Frosts and freezes do look likely for most all locations this month with periods of colder than normal weather. Especially early in the month frosts may occur with a high pressure over the region and a trough.
Precipitation- Precipitation looks to be near normal for the month with a dry start to the month as a strong high pressure looks to be over much of the eastern United States in a general benign weather pattern. Towards the middle of the month and the end the active storm track should resume similarities to earlier in the month of September. The subtropical jet will feature periods of storms tracking up the east coast. As far as snowfall, most likely at some point in the month areas, in the lake effect snow belts of Maryland and Pennsylvania will see at least flurries. It is too early to tell whether any system like October 2009 will affect the region.
"Temperature and Precipitation Outlooks from Climate Prediction Center for next 30 days"
(Courtesy of NOAA)
"Here 10mi Northeast of Harrisburg, PA 2009 Statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 8
Severe Thunderstorm Warnings- 9
Tornado Watches- 0
Tornado Warnings- 0
Total Thunderstorms- 33
Flood Watches- 4
Flood Warnings- 1
Monthly Precipitation- 3.69inches
Yearly Precipitation- 32.53inches
Heat Advisories- 2
Excessive Heat Warnings- 0
90degree Days- 9
Highest Temperature- 95degrees
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.