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Philadelphia Area Weather Forecasts

WEEKEND WEATHER FORECAST

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#Philadelphia #weather #PAwx

Past 72 Hour Rainfall Totals

Posted Sunday 09/29/24 @ 10:31 AM — Through 9 AM Sunday, the MRMS rainfall totals for the previous 72 hours—

MRMS rain-gauge measured rainfall combined with rain-gauge calibrated and interpolated radar-based summary of ACTUAL RAINFALL RECEIVED. Color shading is in inches. Line contour numbers are in mm. (25.4 mm= 1 inch)      (Click on image for a larger view.)

Not much additional rain expected through Tuesday, except in areas shown below.

Sunday Update – Week Forecast Outlook

Posted Sunday 09/29/24 @ 9:55 AM — Humid tropical air in our area overrunning high pressure to our northeast will continue to bring low level clouds, mist and the chance of light drizzle or light rain today, Sunday. Total rainfall looks to be less than Saturday. Northeast wind flow will keep us near 70º.

A break in the action with even some sun possible during the afternoon Monday, especially areas Philadelphia and northeastward, as high pressure builds down.

Low pressure developing along the Virginia coastline had been expected to bring us a decent rainfall Tuesday, but there’s been a consistent trend towards this low being too far to our south, suppressed by blocking high pressure. So very little rain now expected for Tuesday—

09-29-24 06z GFS Total rainfall by Wednesday morning. (Click on image for a larger view.)

A cold front moves through Wednesday. Little additional rainfall here.

Incredibly, the extended range models are strongly hinting at another tropical storm or hurricane in the Gulf next weekend, with a track similar to Helene. The machine learning/AI model ECMWF-AIFS has also been consistently showing a storm forming by next Saturday—

09-29-24 06z ECMWF-AIFS forecast for next Saturday at 8 PM. (Click on image for a larger view.)
Continued Cloudy with Varying Light Showers

Posted Saturday 09/28/24 @ 10:12 AM — Last nights 06z models and this morning’s 12z models continue to forecast low clouds and intermittent light showers through Saturday. Some models show some thinning of clouds in southern Delaware and Chester counties towards evening, but that reverses itself overnight.

There isn’t much change for Sunday according to the RRFS and REFS experimental models.

Here’s the current setup Saturday morning with light showers from very moist southeasterly flow—

Composite Radar at 10 AM with boundary level winds (low level) from the SE (blue contours) and1000-500 mb thickness (yellow contours) (Click on image for a larger view.)

While some models continue with a more substantial rainfall for Tuesday, the GFS is suggesting a further southeasterly development of low pressure which would have the heavier rain miss us. Too soon to tell.

Total Rainfall So Far

Posted Friday 09/27/24 @ 5:44 PM — We need the rain. How much rain have we gotten over the recent days? Here’s the MRMS totals through 4 PM today.

MRMS rain-gauge measured rainfall combined with rain-gauge calibrated and interpolated radar-based summary of ACTUAL RAINFALL RECEIVED. Color shading is in inches. Line contour numbers are in mm. (25.4 mm= 1 inch)      (Click on image for a larger view.)

Quite a range of values over our region!

Originally Posted Fri @ 5:01 PM — —The remnants of Hurricane Helene continue to rotate into and merge with an upper air low over Tennessee.

Considerable moisture is being flung up towards Philadelphia from the south and southeast around this combined system and as it hits a high pressure ridge just northeast of us, the moisture is riding up over it and condensing out as rain.

Friday afternoon satellite water vapor image with superimposed RAP model 500-1000 mb thickness lines (yellow), Mean Sea Level Pressure isobars (black contours) potential vorticity (fine violet contours) with superimposed MRMS RADAR. Low pressure at the surface will rotate and merge with upper level low (blue L) Moisture on east side will rotate into our area . (Click on image for a larger view.)

By Sunday afternoon, the upper low will have remained almost stationary, but will begin to move eastward and perhaps induce a surface low off the coast for Tuesday—

09-27-24 12z GFS forecast for Sunday at 2 PM. Secondary coastal low possible by Tuesday. (Click on image for a larger view.)

Saturday Forecast

Low clouds. areas of fog possible early, with showers likely throughout the day, widespread in the morning, more scattered and light in the afternoon.

NBM high temperatures: Blue Bell 73º Philadelphia 76º
Above Average Uncertainty (based on standard deviation): ± 2.4º

Sunday Forecast

Low clouds, fog, some sprinkles early, then cloudy in the afternoon but little in the way of additional showers.

NBM high temperatures: Blue Bell, 69º Philadelphia 71 º
Above Average Uncertainty (based on standard deviation): ± 2.7º

A break in the rain on Monday, widespread rain likely on Tuesday.

Birds & Wildlife

PARAKEETS ON THE SCHUYLKILL?

#Philadelphia #Wildlife

Last year, specifically November 30th, 2023, while bicycling on the Schuylkill River Trail, we noticed several tropical parakeets in the vicinity of the old railroad bridge just west of the Norristown Train Station. I never posted the sighting, because I couldn’t get a good picture, but this is what I had captured on my iPhone at the time last year—

November 30 2023 along the Schuylkill River Trail (converted old railroad bridge of the trail just west of the Norristown Train Station)

We were biking again this past week, and incredibly, we saw another parakeet in the same general vicinity of the last sightings, just a bit further west along the trail—

Tuesday, Sept 24th 2024, slightly further west from the converted train bridge on the Schuylkill River Trail

Here is a video of the same sighting this week—

Tuesday, Sept 24th 2024, slightly further west from the converted train bridge on the Schuylkill River Trail

I bike on the trail quite a bit. This is the second year seeing parakeet(s) in the Fall, on this trail. I haven’t noticed these birds any other times of the year.

Perhaps we’re seeing a trend that has occurred in cities in Europe. Check this story out. And this story says that escaped pet parakeets have naturalized in many cities in the US. Who knew?