Timing This Morning's Rain & Wind

<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEibAKW0rr9jC3apzsgdcFvcqhKp5HcaUQzho8lKJzvqOx9ptp6xkEI0CcrmLz820Bhw7ZNtZo-nDIA-KuDmpn6kBzY1JNhyw497m2a0cRo48-afa76zKbj0cenG4RnF-vpNOmvFkhJs5KA3/s1600/110113-STW.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="348" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEibAKW0rr9jC3apzsgdcFvcqhKp5HcaUQzho8lKJzvqOx9ptp6xkEI0CcrmLz820Bhw7ZNtZo-nDIA-KuDmpn6kBzY1JNhyw497m2a0cRo48-afa76zKbj0cenG4RnF-vpNOmvFkhJs5KA3/s400/110113-STW.jpg" width="400" /></a></div><br />A severe thunderstorm watch is out across Central Pennsylvania until 10 AM with a squall line of wind and rain but little in the way of thunder pushing east through the state. This will work towards us and cross the region later this morning. However, modeling does suggest that this line weakens a bit before it gets here.  That said, the potential for gusty winds does prompt the Storm Prediction Center to issue a watch until 11 AM for the city and points north and west.<br /><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj2bWb_keeTtq21o2bxAnnjGnSmLhuRorGhTFmD1z18T2pEyUzVwI5XoAQurw01swtpB51naET9s7CFZd4c2xR_REcxGjMk7UZPu-wb_XZTUCkesN_JyinvnlXuRT0kIywC9HM-d-Kw2d_Y/s1600/110113-STW3.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj2bWb_keeTtq21o2bxAnnjGnSmLhuRorGhTFmD1z18T2pEyUzVwI5XoAQurw01swtpB51naET9s7CFZd4c2xR_REcxGjMk7UZPu-wb_XZTUCkesN_JyinvnlXuRT0kIywC9HM-d-Kw2d_Y/s400/110113-STW3.jpg" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Severe Storm Watch until 11 AM.</td></tr></tbody></table><br /><br />Until the frontal line gets in and through the region, expect a breezy and at times windy go of things this morning in the Delaware. Rain will move through in varying levels of intensity, mostly light to moderate ahead of the front.   Winds will gust to over 40 miles per hour ahead of the front, sustained in the high teens and low 20's...and it will feel semi-tropical out.<br /><br />Timing the front, it appears we should see the band approach the western burbs by 8 AM, crossing the city over the proceeding hours thereafter. With the band of showers, rain could pick up briefly in intensity with the front itself as will the wind. We could see some 50 mile per hour gusts locally but I think the best chances for that stay north and northwest of the city (where dynamics and storm support are a bit better).<br /><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhaGSRlIyNGWv9twigYtebmSmG-A95zt9C57KeaHY5izMl_KEuXwWQWHoXPmX2WLckpAxl8JmlcGmRD9_ZDtMy6_u9hq7dkjKLBh7P4yTMuURb2Vbsiaxjk-ggyYrHR48YBBiUz-nxQkfda/s1600/110113-STW2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhaGSRlIyNGWv9twigYtebmSmG-A95zt9C57KeaHY5izMl_KEuXwWQWHoXPmX2WLckpAxl8JmlcGmRD9_ZDtMy6_u9hq7dkjKLBh7P4yTMuURb2Vbsiaxjk-ggyYrHR48YBBiUz-nxQkfda/s400/110113-STW2.jpg" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">HRRR guidance for 9 AM showing what's left of the Fall Squall moving in. Guidance has been a bit slower than reality in terms of timing.</td></tr></tbody></table>Dynamics are stronger out to our west, which is allowing the frontal squall to strengthen across Central PA. Those wind dynamics aren't as 'good' here, which suggests the line should weaken a bit as it crosses the region. That said, the risk for strong winds will continue through the morning, with the frontal boundary band moving through between 9 and 10 AM in the city, 10 AM and 11 AM east of Philly.<br /><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhankk6ewD2xLHvj-fnyEtIXZkfjn_Z4LrnSFQgph2TZDf__OVFns_J-X_9X-pxV0wLGWQj8E-SQyNZVL_2ZBIc8mNqEq627Xu6itS62kVGWrsAfrHdGigVXl-VvrkJ892x_XNfwz8U536G/s1600/110113-STW3.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhankk6ewD2xLHvj-fnyEtIXZkfjn_Z4LrnSFQgph2TZDf__OVFns_J-X_9X-pxV0wLGWQj8E-SQyNZVL_2ZBIc8mNqEq627Xu6itS62kVGWrsAfrHdGigVXl-VvrkJ892x_XNfwz8U536G/s400/110113-STW3.jpg" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">HRRR at 1 PM. Most shower activity has come to an end.</td></tr></tbody></table>By 1 or 2, most of the shower activity will be winding down through the region. Sunshine should break out west of the city, gradually working its way east through the balance of the day.<br /><br />More: <a href="http://current.phillyweather.net/" target="_blank">Current Radar</a>

fall squall gusty winds Timing This Morning's Rain & Wind

A severe thunderstorm watch is out across Central Pennsylvania until 10 AM with a squall line of wind and rain but little in the way of thun...

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Friday Morning's Commute Looks Wet, Windy

There's a mixture of good news and not-so-good news for you this morning in the weather department.<br /><br />First, Halloween looks dry and mild for those who are looking to get out and get candy, or accompany the young ghost, goblin, or assorted costume character (please for the love of humanity, avoid going as Miley Cyrus). There could be a shower or two out towards Harrisburg or up towards Scranton but for those of us here, should be dry and mild.  Temperatures will likely be in the 60's tomorrow night for a good chunk of the evening with a mild southwesterly breeze. Not quite "shorts and t-shirt" weather but pretty nice for the end of October.<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh818Pli052GL8Ci7Jnm1K_g9WDhQfjABXxz7YxVpM4eJ7OawMgSf3-SygBC-xWGfigZGtnzJoEFfNv19GuKLSRgPztlgLnfxVygMoPskyh4FQu_yoynWsMx5ebcI1H2Sxn8I39cC2o2Ppb/s1600/103013-AM1a.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh818Pli052GL8Ci7Jnm1K_g9WDhQfjABXxz7YxVpM4eJ7OawMgSf3-SygBC-xWGfigZGtnzJoEFfNv19GuKLSRgPztlgLnfxVygMoPskyh4FQu_yoynWsMx5ebcI1H2Sxn8I39cC2o2Ppb/s400/103013-AM1a.jpg" width="400" /></a></div>That's all brought to you by an approaching cold front that's going to move through on Friday with a pre-frontal band of rain and perhaps thunder. That mass of rain and isolated thunder moves in after Midnight tomorrow night, pushing through for the morning commute before departing. In addition to the rain will be an increasing breeze on Thursday night as winds at 5000 feet up will push above 70 miles per hour, higher north and west of the city, towards daybreak Friday. Those winds don't all transpose to the surface but in heavier showers we could see some 40-50 mile per hour gusts, perhaps a bit higher on ridge tops in the Poconos. It would not shock us to see a severe "thunderstorm" warning or two fire up tomorrow night and early Friday because of those winds.  Thunderstorm is in quotes because the line of rain and wind may not contain much, if any, thunder at all.<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhQmOmTVbhV32ht4g-F-WovA1UPCAFmtiEorU3iXbIUaA6jBtDRIY1o5ShWI9oRZ_hPBm40606RXoO6twSAt4A0zzaO1WytP8XGNsNiYGJmu8JT_x3ehw9HKnLTRLd3ME-O8F9LsYtTjiv6/s1600/103013-AM1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="267" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhQmOmTVbhV32ht4g-F-WovA1UPCAFmtiEorU3iXbIUaA6jBtDRIY1o5ShWI9oRZ_hPBm40606RXoO6twSAt4A0zzaO1WytP8XGNsNiYGJmu8JT_x3ehw9HKnLTRLd3ME-O8F9LsYtTjiv6/s400/103013-AM1.jpg" width="400" /></a></div><br />This frontal boundary and storm system will produce a higher risk of severe weather back across the Ohio Valley and Western Pennsylvania than locally as instability parameters will be a bit better to our west than locally, thanks in large part to timing. That said, there's enough wind energy with this storm system despite the timing to probably get some 40+ mile per hour wind gusts with the frontal squall as it moves through.<br /><br />Rainfall should average out to about a half an inch regionwide, a bit more north than south.<br /><br />Temperatures on Friday morning could be in the mid, perhaps upper, 60's across a large chunk of the region. This may help us pull off a second 70 degree day in a row to start November as tomorrow looks like we should get to 70 in the city.

fall squall GFS Halloween weather NAM Friday Morning's Commute Looks Wet, Windy

There's a mixture of good news and not-so-good news for you this morning in the weather department. First, Halloween looks dry and mild ...

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Storm System For Thursday Night Into Friday

A tranquil and relatively mild week is ahead of us for the Delaware Valley but a stronger storm system lurks in the forecast for Thursday Night into Friday. The GFS has maintained strong consistency so far in suggesting a frontal passage in the overnight Thursday into Friday timeframe, with the Euro a bit delayed in timing (Friday evening). Given the track, it will be a warm, breezy setup for us as temperatures likely push 70 on Thursday.<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2K_bUXOCYUVaCNpSlvKVOBszHrltptNVv6sg4tK2V6aIqkIlv7l9e83OAcrc_5eZ2mhb6H1o0d6-m-n1Ei61T8r1C42QBNWTLX_1NbTiTwiK19qS1P13f2XLRraA4wjx1AkkVQOPsdHEK/s1600/102713-FRONT.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2K_bUXOCYUVaCNpSlvKVOBszHrltptNVv6sg4tK2V6aIqkIlv7l9e83OAcrc_5eZ2mhb6H1o0d6-m-n1Ei61T8r1C42QBNWTLX_1NbTiTwiK19qS1P13f2XLRraA4wjx1AkkVQOPsdHEK/s400/102713-FRONT.jpg" width="400" /></a></div><br />The specific details of what accompanies the front will still be ironed out but at minimum we will have a breezy Thursday night into Friday, with the prospect of a gusty squall line of wind and rain pushing through with the front itself.  Modeling shows some pretty strong winds (see below) at 5000 feet up. The GFS model suggests that winds could reach 60 or 70 miles per hour aloft, with some of that possibly translating to the surface as the front pushes through.  With an evening or overnight timeframe, we may have a bit more of a struggle in getting a portion of high winds down to the surface as the atmosphere's lowest levels may be a bit more stable.  That said, gusty winds of some sort probably accompany this front, along with a band or two of rain.<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_HGQPaoqL9gZMG2sl_9ERHy6GyTN530pYBgEUVUejfS-tT1DvJRcBma2t6pE1osQH6hKEHBmNNX_QqoYgPVNOo-deKpVdh97hHahPONoh6w_P8fCWpaJr60OwEMzL1z1oj1t4XO4rBy2F/s1600/102713-FRONT2.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_HGQPaoqL9gZMG2sl_9ERHy6GyTN530pYBgEUVUejfS-tT1DvJRcBma2t6pE1osQH6hKEHBmNNX_QqoYgPVNOo-deKpVdh97hHahPONoh6w_P8fCWpaJr60OwEMzL1z1oj1t4XO4rBy2F/s400/102713-FRONT2.jpg" width="400" /></a></div><br />Post-front, a cooler weekend is in store on a gusty west-northwest flow. Temperatures probably end up dropping back into the 50's for highs.

computer model discussion fall squall frontal boundary Storm System For Thursday Night Into Friday

A tranquil and relatively mild week is ahead of us for the Delaware Valley but a stronger storm system lurks in the forecast for Thursday Ni...

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