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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · 29d

In the September 17th to 23rd outlook, the below normal precipitation outlook has been pulled north signaling a push of moisture into the SW PA region. During this period, Sept 20th and 21st have a decent chance for a 0.10 or more of precipitation.

This graphic shows the precipitation outlook compared to climatology for Sept 17 - 23.

This graphic shows the probability of 0.10 or more of precip. Highlighting the 20th and 21st of September.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · 29d

Dry conditions and mostly sunny skies continue today with temperatures still trending up. Highs will end up right around normal this afternoon.

Image showing the the high temperature forecast for today.

NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · 29d

So....Canaan Valley ended up "winning" for lowest temperature in the CONUS on the 9th.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · 29d

Meteorologists use a different accounting of the seasons than the astronomical cycle, by starting the season at the beginning of a month. This aligns with the yearly temp cycle while also keeping records consistent - astronomical season start dates can vary from year to year.

Image showing the differences between astronomical and meteorological seasons.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 9

Here are locations where national high/low temps were observed in 2023 and 2024 (larger circle = greater number of occurrences).

Canaan Valley, WV gets the award for lowest national temp a few times a year, mostly in the spring and fall on clear and calm nights like these.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 9

Canaan Valley tied for coldest observation site yesterday morning, and it looks like they may have a chance at being the coldest in the US today seeing that they are currently sitting at 23F this morning.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 9

Piggybacking on a recent post, here is a comparison of hourly temperature departures from normal back to 1973 at Pittsburgh International Airport. The one on the left is the hourly temperature departure from normal with clear skies, and on the right, mostly cloudy conditions.

Image showing the differences in daily temperatures fluctuations in Pittsburgh compared to cloud coverage.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 8

If you're not enjoying the cooler weather, you'll be pleased to know that a pattern shift is anticipated at the end of the week, bringing near to above-average temperatures back for the weekend.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 8

A daily record low was set at DuBois, PA today at 37°F degrees. This breaks the old record low of 38°F set in 1986.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 8

Wildfire safety refresher! Many everyday things can spark wildfires. Keep ignition sources far away from dry vegetation, wood and other fuel. Be aware of weather conditions. Always follow burn bans & local, state, and federal regulations. http://weather.gov/safety/wildfire-ww #WeatherReady

Everyday Wildfire Prevention. Most wildfires are caused by humans - many everyday things can create sparks. Keep ignition sources far away from dry vegetation, wood, and other fuel. Have a clear 10 foot radius around campfires, burning brush, etc. Never leave fires unattended, and always properly extinguish. Use grills and smokers on gravel or paved surfaces. Never toss lit cigarettes on the ground. Put ashes in a metal container with a tight lid. Keep water stored near campfires, fire pits, grills, smokers, burning brush, etc. Maintain vehicle brakes & tires, and secure tow chains to avoid dragging. Don't drive on dry grass or brush. Water your lawn and keep grass cut. Mow lawn early in the morning and when it's not windy or excessively dry. Always follow burn bans and regulations. Be aware of weather conditions. Low humidity, heat, drought and winds are conducive to fires.

NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 8

Most of us have seen 25-50% of our normal precipitation in the past 30 days and there's no rain in the forecast for at least the rest of this week. During a drought, stay Weather-Ready by conserving water and practicing fire prevention. http://weather.gov/safety/drought

NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 8

Dry conditions and a gradual warming trend (can be expected over the coming week, with large diurnal variations (~90th percentile) in low/high temperatures as minimal cloud coverage allows for efficient overnight cooling.

High and low temperatures through Friday. and average diurnal curves for Pittsburgh during the second week of September

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 7

With clear skies and cool upper air, a chilly Monday morning is anticipated.

Temperatures will likely fall into the low 40s to upper-30s across the region between 2am and 7am tomorrow morning.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 7

It will be a beautiful day for most today under partly cloudy skies with highs around 10 degrees below normal. Chances of scattered showers only linger for the I-80 corridor.

Todays forecast map with images of clouds and sun pictured over a map with forecast high temperature in the upper 60s to low 70s. A rain icon is displayed only over the I-80 corridor.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 7

Dry conditions and a gradual warming trend (from 10 degrees below normal to normal/slightly above normal) can be expected over the coming week.

Image showing probability of precipitation

NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 7

There's a low chance of rain over the next few day, with a slight possibility of lake-enhanced precipitation tomorrow for areas north of Pittsburgh. Temperatures are expected to be cool tonight and tomorrow, then warm up through the week.

High temperatures will range from the mid-60s to low 70s Sunday into Monday before climbing into the upper-70s and low-80s Tuesday into Sunday.

Overnight low temperatures will be int he 40s to low-50s Sunday into Wednesday; upper-40s to mid-50s Wednesday into Sunday.

Precipitation chances will be very light over the next 7 days across the region. Less than 0.10 inches is likely.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 6

Westerly dry air is helping to clear the thick cloud cover, and sunshine is already breaking through in parts of eastern Ohio.

NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 6

After today (tomorrow for the I-80 corridor), hopes look pretty grim for rain over the next week with high pressure in place. Do you like dry fall weather or do you prefer the rain?

Chance of rain at various cities in the forecast area over the next week as a line graph.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 6

Two rounds of showers (one in the morning and one in the afternoon) will bring mostly light rain to the area today. The 1st wave will favor areas east of the OH/WV border; the 2nd will favor cities SE of Pittsburgh. Temperature today will be ~10 degrees below the daily average.

Table showing fluctuating precipitation chances for select cities at hourly intervals until early Sunday morning. Text notes two different rounds (morning and afternoon) of rain, each becoming progressively more eastward in impact.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 5

Isolated storms are starting to fire up ahead of the cold front that stretches down into West Virginia and Kentucky. The best opportunity for strong to severe storms in our area will be over the next 4 hours.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 5

Showers and possible thunderstorms are expected tonight into part of Saturday with a crossing cold front.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 5

Partly cloudy skies and warmer temperatures are expected today.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 5

Areas of fog have developed across the region, with a Dense Fog Advisory in effect until 9am for portions of western PA. If you are out driving, exercise caution as visibilities could be reduced to less than 1/4 mile.

Visit your state's DOT site for the latest road conditions.

Graphic highlighting best practices if driving through dense fog.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 4

There is another day with the potential for severe weather on Friday. The main threat will be damaging winds. The timing will feature storms entering the forecast area by 7-8pm and crossing the Pittsburgh area by 9pm-10pm.

The graphic shows the outlooked area in a Marginal.

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NWS Pittsburgh (Unofficial Mirror) @nwspittsburgh.bsky.social · Sep 4

4:31pm: Our office has recorded 0.64" of rain so far today. This is the most we've seen since July 16th!

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