A Bit of Snow and Frigid Temperatures this Weekend

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Edit: Holy moly! Way more snow than expected! The model runs late last night did a bit better with snow totals, but they still underproduced. We’ve been dry lately so I can’t argue with some extra snow.

After a bit of moderate weather over the last few days, we’re heading into another arctic air outbreak that will bring us some snowfall along the front range and low temperatures in below zero with pretty severe wind chills. So, if you’re embarking on a journey away from your home to buy Christmas presents, go to the Broncos game, or just down the street to get groceries, be prepared for slippery conditions and very cold temperatures!

Today’s forecast will be broken into the following sections-

  1. Current Conditions
  2. Storm System Timing
  3. Expected Low Temperatures
  4. Expected Snow Totals
  5. Summary

Current Conditions

brrrr

Large drop in temperature at Marshall, Colorado at ~14:00UTC, which is 7:00am MST. A cold front passage caused the drop and the continuing decrease.

As you can see in the plot above, we experienced a powerful cold front at 7am that dropped temperatures around the metro area 20°F in the course of about thirty minutes. Along with the cold front came some intense winds that are gusting up to 25mph at the airport and are causing wind chill temperatures that hover right around zero. Currently there aren’t a lot of clouds hovering overhead and there aren’t any snowflakes to be be seen… yet.

Storm System Timing

Obviously, we’ve already started down the path of our winter storm with the cold front that passed through earlier this morning. As we continue through the day, our sunny skies will change to that familiar grey that means snow is on its way. Sunset is currently looking to be the time when cloud cover and chance for snowfall really increases. Snowfall around Denver will begin this evening and will continue through tomorrow morning. The frigid temperatures, however, will be sticking around all weekend until we return to highs in the 40s on Monday.

Expected Low Temperatures

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Expected low temperatures across the region on Saturday night

Low temperatures are expected to be between 0°F and -5°F for most of the metro area tonight with wind chills that could reach as low as -20°F. Saturday night is expected to be a few degrees colder, but winds are expected to be lighter which means wind chills should remain roughly the same. At this point in time, it looks like our low temperatures will be a few degrees warmer than the record lows for the metro area but there’s always a possibility that will change. Regardless of whether they’re record-breaking or not, please keep your pets inside, dress in layers, and have an emergency kit in your car with a blanket. It doesn’t pay to gamble with these cold temperatures!

Expected Snow Totals

This storm is shaping up to be similar to the last arctic storm that we had which means that we’re looking at 1-3″ for most areas (I know, it’s not thrilling). Denver and the immediately surrounding cities should expect 1-3″ while areas to the south and west can expect 2-4″. Contrary to popular belief, lower temperatures do not mean more snow. In fact, it’s the opposite. Cold air cannot hold as much moisture as warm air and so we get small accumulations with arctic storm systems. This is also why we get lots of snow from our spring blizzards, the warmer air can hold more moisture and dump it on us!

Regardless of how much snow we get, it could be very icy on the roads tomorrow.

Summary

Snow will start this evening and will continue through Saturday morning with accumulations for most areas around 1-4″. Temperatures will continue to fall over the next two days and many areas will see below-zero temperatures tonight and Saturday night. Wind chills will be extreme and could be as low as -20°F overnight, which means that precautions should be taken if you need to go outside. These severe low temperatures will continue through Sunday, but 40s will return on Monday.

Thanks for reading! Let me know if you have any questions!

-Andrew

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Warmer Temperatures for Denver, Feet of Snow in the Mountains

A brief Denver update, but the main purpose of this is to describe the return of snow, beautiful-beautiful-large-amounts-of-snow, to the forecast for the mountains.

Denver Current Conditions and Near Future Forecast

It is still very cold outside and temperatures will only reach the upper teens and low 20s today around the metro area. Overnight we had a low temperature of -8°F in Denver with a wind chill value -25°F when our winds reached a maximum of 8kts (~9mph) at 11pm at the official Denver weather station at DIA. Luckily, the wind died down as the night progressed and, while the temperatures remained low, the wind chill became less of a factor. Right now, Denver is sitting at roughly 5°F and we should reach highs in the upper teens and low 20s.

Our recent cold snap comes to an end tomorrow when temperatures will climb into the mid-40s and will be around 50°F on Saturday. We will have another slight chance at some light snowfall on Sunday morning as another weak storm system moves through Denver, but accumulations won’t add up to much. While temperatures will again drop next week, they will be close to seasonal temps and will be in the 30s and 40s.

Mountain Snow Forecast

This is the main reason that I decided to make a post today. Break out the skis and wax the board! Great shredding is coming our way! I did a quick overview, described a couple regional forecasts, and a brief word of caution. Check it out!

It finally looks like big precipitation amounts will be coming to the mountains. Current models have loads of moisture coming from the Pacific and impacting most of the western US with the Colorado mountains getting up to five FEET of snow in some areas over the next two weeks. In fact, some areas of northwestern Colorado are expecting over 60″ of snowfall in the next seven days! Overall, most areas along I-70 are looking at 18-36″, but it’s possible that we could see up to four feet of new snow on the taller peaks in that time.

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Total snowfall from today through 6pm MST December 22nd, 2016. Notice the 51.7″ amount near Routt County in Northwestern Colorado.

Regional Mountain Forecasts

Medicine Bow/Routt National Forests Including Steamboat Springs

It looks like the Northwestern part of Colorado will be getting the best snow over the last two weeks . Below if a graphic that shows the Quantitative Precipitation Forecast (liquid precipitation in inches) as well as the expected snow totals for the GEFS, CMCE, and NAEFS models. If this forecast were to verify, over five feet of snow will fall in the next seven days! THAT’S “WEEK” SINGULAR! Steamboat Springs and Rabbit Ears Pass are starting to sound pretty good, aren’t they?

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Forecasted QPF and snowfall amounts for Medicine Bow/Routt National Forests over the next week. Thanks to the University of Utah for the graphic.

I-70 Corridor

The I-70 corridor is not going to see the same insane amount of snowfall over the next week that Steamboat will. However, there will still be plenty of snowfall over the next week and even more over the next two weeks (3-4 feet expected through the 22nd). Right now, this area is looking at roughly 18-24″ of snow over the next week depending on where you’re targeting on the forecast map. As an example, Vail Pass is expecting upwards of 24″ of snow over the next week while areas slightly to the east are expecting closer to 18″. Still, that’s some great snow when the earlier part of the season had been very dry.

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Forecasted QPF and snowfall amounts for Vail Pass over the next week. Thanks to the University of Utah for the graphic.

A Word of Caution

We are all aware that models fluctuate frequently and these totals are anything but set in stone. However, to see this amount of precipitation in the forecast does give me hope and, at the very least, we should see some good snowfall over the next two weeks. Will it be five feet in a week? That’s hard to say, but multiple models are liking the chances of big snow from the next few storms. We’ll have to wait and see, but the mountains could just be an amazing place to be over the next few weeks!

Thanks for reading!

-Andrew

Final Forecast- Timing, Snow Totals, and Temperatures for the December 6th Snow Storm

I’ve been keeping a close eye on this storm for quite a while leading up to today. The promise of snow and possibility of below zero temperatures after a summer that was seemingly endless filled me with endless amounts of excitement. Then again, I’m a winter person and I love cold weather, your feelings about this storm system may vary. Regardless of whether you’re excited about the cold and snowy weather, it has arrived and will make things treacherous over the next 24 hours!

Today’s forecast will be broken into the following sections-

  1. Current Conditions
  2. Storm System Timing
  3. Expected low temperatures (possibly record-breaking)
  4. Expected Snow Totals
  5. Summary

Current Conditions

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Visible satellite image 9:15 MST December 6th, 2016

The front range has clear skies and that has contributed to low temperatures in the low teens and even around 10°F over night.In fact, most areas are still hovering right around the 10°F mark currently, but negative temperatures lie just to our north in Wyoming and they will make their way down here by tomorrow tonight. Cloud cover is positioned over the western part of the state and, as this storm system makes its way from west to east, the front range will eventually become cloudy later this morning and afternoon as well.

Storm System Timing

Obviously this system has already started to come through the state with our big drop in temperatures over the last 24 hours and high winds last night (that reached 75mph at the NCAR Mesa Lab!). The snow associated with this storm system should start making its way  into the metro area late-afternoon around 5-6pm and will continue through most of the day tomorrow. Initially, snowfall rates will be light but should start picking up intensity around rush hour this evening. The heaviest snowfall rates should occur late tonight between 9pm and midnight while light snow and flurries will continue through much of tomorrow.

Expected low temperatures (possibly record-breaking)

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Forecast Temperatures at 5am MST December 08, 2016

The real story with this storm won’t be the snow totals, but the dangerously low temperatures that we’ll encounter tomorrow night (and tonight to a lesser degree). Lows around the Denver metro area are expected to dip down below zero and will be between -5°F and -10°F for most areas with wind chills that could be between -15°F and -20°F on Wednesday night. Tonight, we’ll still be cold with temperatures in the single digits and wind chills possibly below zero, but the clouds will help keep some heat near the ground whereas tomorrow night, they will not. These are dangerous temperatures and should not be taken lightly. Make sure to keep your pets inside and dress warm and in layers if you have to go outside. Also, make sure that you have an emergency kit in your car that includes a blanket. It will only take 30 minutes to incur frostbite on exposed skin in these temperatures!

Expected Snow Totals

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Global Forecast System (GFS) 12Z run Snowfall Totals through 8pm MST December 7th, 2016

I’m expecting 2-5″ for most areas around the front range with slightly higher amounts of 3-6″ along the foothills and more as you venture into the mountains. Bear in mind that this is 2-5″ of snow by Wednesday night. This has been a particularly challenging forecast because of the cold temperatures that will be associated with the snowfall.

Cold temperatures mean that we can get more snowfall accumulation from similar amounts of water. As an example, think of the champagne powder that falls in the mountains. It’s light, fluffy, and very “dry” snow which allows it to move easily and create those brilliant powder clouds that shoot over your head when skiing or snowboarding. By comparison, think about spring storm snowfall. It’s wet, heavy, and incredibly difficult to shovel when it accumulates on your sidewalk.

It all comes down to what is known as the snow to liquid ratio (SLR), which gives a certain amount of snow accumulation per inch of liquid water in the atmosphere. Generally we use a 10:1 ratio which means that we get 10″ of snow to 1″ of water that falls. However, spring storms can be as low as 6:1 or 8:1 and very cold winter storms can be as high as 20:1 or 30:1. For this storm, I’m expecting a SLR of approximately 20:1 due to the low temperatures. This means that we’ll see light and fluffy snow out of this storm and it won’t have a ton of moisture (easy shoveling!). Colorado needs all the precipitation that it can get!

Summary

Snow will arrive in town early this afternoon and will continue through Wednesday afternoon. While 3-6″ of snow are expected in most areas, the real hazard will be the dangerously low temperatures in single digits tonight and below zero tomorrow night. Snowfall rates will be most intense over night tonight, but light snowfall will continue through tomorrow and will make commutes slippery and dangerous. Again, make sure that you have an emergency kit in your car and stay warm, friends!

Thanks for reading! Feel free to comment or ask any questions!

-Andrew

Brief Outlook- Bitter Cold and Snow for Denver

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Temperature at the National Center for Research Winter Weather Test Site in Marshall, Colorado (Just south of Boulder)- December 05, 2016

Edit: Ignore the (C) on the y-axis of the plot. It’s actually in Fahrenheit but the axis title didn’t chance.

Denver and the surrounding regions have already started to cool off dramatically after the passage of a cold front earlier that has caused temperatures to drop ~14°F in the last few hours. We’re still about 10°F warmer than tomorrow’s expected high temperature of 28°F which means that we still have a lot of cooling off to do tonight. In fact, we’re going to be dropping into the low teens this evening. A Winter Weather Advisory has been issued by the National Weather Service and can be found below.

Winter Weather Advisory-

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOWFALL, WHICH IS IN EFFECT FROM 5 PM
TUESDAY TO NOON MST WEDNESDAY.

* TIMING...LIGHT SNOW WILL START TUESDAY AROUND RUSH HOUR AND
  INCREASE IN INTENSITY BY TUESDAY EVENING AND CONTINUE THROUGH
  WEDNESDAY AFTERNOON.

* SNOW ACCUMULATIONS...SNOWFALL AMOUNTS OF 2 TO 5 INCHES WILL BE
  POSSIBLE WITH HIGHER AMOUNTS WEST OF I-25

* WIND/VISIBILITY...WINDS WILL BE LIGHT THROUGH THE
  PERIOD...HOWEVER SNOWFALL INTENSITY WILL INCREASE TUESDAY NIGHT
  AND CREATE FOR SOME REDUCED VISIBILITY.

* IMPACTS...MAIN IMPACTS WILL BE HAZARDOUS DRIVING CONDITIONS WITH
  INCREASING SNOW INTENSITY TUESDAY EVENING TOWARDS THE END OF
  RUSH HOUR. CAUTION IS ADVISED FOR DRIVERS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

As we edge closer to the storm system that will impact us tomorrow and Wednesday, some things are clear and others are still a bit fuzzy. What we know is that we will see a pretty drastic change to our weather that has been relatively mild over the last few days and we’ll wind up with frigid temperatures and snow arriving in Denver tomorrow afternoon and continuing through Wednesday. However, we still don’t know just how much snow we’ll actually be getting. There is a bit of disagreement between models, but the overall consensus is that it’s looking like 2-4″ of snow for most areas around Denver that will fall primarily between late afternoon/evening tomorrow through Wednesday morning. Snowfall will be relatively light, but heavier areas in the foothills, mountains, and to the east of Denver are expected.

A more comprehensive forecast will be available tomorrow morning so make sure to check back!

Thanks for reading!

-Andrew

Denver Parade of Lights 2016 Forecast

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A joyful family enjoys their local Christmas Parade in Hohman, IL. Through an unprecedented  string of good luck earlier in the month, the father had received a “major award” and their son was recruited to help with the rigorous decryption of important messages. (1940, colorized)

Tonight’s the night! The 2016 Denver Parade of Lights will march past the Denver City and County Building and through the streets of Downtown Denver. First-nighters, packed earmuff-to-earmuff, will jostle in wonderment before a golden, tinkling display of mechanized, electronic joy!

Floats, marching bands, and all sorts of wild acts will fill the streets of Denver to the delight of children and adults-who’ve-had-too-much-hot-chocolate-and-Peppermint-Schnapps alike! However, what will the weather be and what will I need to wear if my Schnapps doesn’t keep me warm enough?! Don’t worry! I’ve got you covered.

Parade Tonight

Tonight’s parade and festivities will definitely be cold as will tomorrow night as well. We’ll be sitting around 26°F when the parade kicks off at 8pm and by the time it ends at its last point around 9 or 10pm, we’ll be around 21°F with wind chills as low as 17°F. Now, bear in mind that these are wind chills for all of Denver and that the winds are really amplified by the tall buildings downtown which means that the temperatures could feel another 5° colder. Some light snow is also possible late this afternoon and early this evening which means road surfaces could be wet or icy. Make  sure that you plan ahead and give yourself extra time, if needed.

Parade Tomorrow

With an earlier start and a sunny day ahead of it, temperatures at the kickoff of the parade tomorrow should be about 10° warmer than they will be tonight at 36°F and a balmy (in comparison) 30°F at the end of the parade. With that being said, there is a higher chance of wind chills tomorrow that could make the forecasted temperatures feel about 5° colder than reality. Tomorrow’s ramp up to the parade promises to be drier as well with sunny skies to get rid of any moisture left on the concrete and asphalt surfaces. It should make for easier watching with the ability to sit on the sidewalk for the kiddies.

christmasstory_pg01

A young boy fulfills his dream of speaking with Santa about his love of football only to realize, after the conversation, that his real desire is weaponry.

Summary

Overall, it will be cold for either parade and they both will require bundling up and hand warmers. However, the parade at 6pm tomorrow looks to be a little warmer and, more importantly, drier. We all know how hard it is to stay warm if you’re wet and it will be downright impossible if you’re wet and temperatures are in the 20s and 30s. So, if warmer weather is a factor for your voyage to the parade, tomorrow might be the best route. If you’re like me and enjoy pretending that you’re lost in a arctic wasteland and the only salvation is the soft glow of electric sex gleaming in the… ok, that Christmas Story quote doesn’t work here. Let’s try that again. If you’re like me and enjoy pretending that you’re lost in a arctic wasteland and the only salvation is the soft glow of electric lights and the anxious anticipation of seeing Santa in his sleigh, Friday might be right up your alley.

Thanks for reading! As always, feel free to ask questions and I’ll answer as quickly as possible.

-Andrew

First Snowfall Forecast

The day of infinite glory is upon us! Our first snowfall of the 2016/2017 winter is falling in a few places along the front range. The mountains will be getting their fair share of the white fluffy stuff as well as they get some much neededermahgerd relief from the incredibly dry and record-breaking hot weather of the last month.

Assuming that the forecast isn’t completely wrong, we will have our first measurable snowfall of the season just four days before we would have broken the record for the latest first snowfall in Denver history. While this storm isn’t going to dump feet of snow or have you on the couch for days drinking hot cocoa and watching Netflix (it might, who am I to tell you what to do with your life), it is going to give us much needed moisture. For many of us though, this storm is not about the moisture in an increasingly dry year, it gives us  some peace of mind that winter has not forgotten us. It’s a simple reminder that we are, indeed, marching forward towards the holidays, skiing and riding the mountains, winter breaks from school, and that we’re not just stuck eternally in an endless late summer. How sweet it is!

Anyway, this is going to look like a fairly normal forecast and will be broken down into these categories-

  1. Current Conditions
  2. Storm System Timing
  3. Expected Accumulations
  4. Summary (If you don’t want the specifics, skip to this one!)

 

Current Conditions

Yesterday afternoon we experienced a cold front coming through the area that has kept our temperatures falling for about 12 hours now. Current temperatures are in the mid-30s around the front range and humidity has increased steadily. Yesterday’s cold front brought plenty of cloud cover as we can currently see blanketing the metro area in a wonderful sheet of grey this morning. Snow and rain have just barely started making their way onto the front range and can be seen on the radar image below. Right now we can see plenty of snowfall in the mountains and, although there is some green in areas like Longmont, Westminster, and to the west of Boulder, that is most likely radar noise and not actually rainfall.

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Radar Image: 10:00am MST Nov 11, 2016 — Blue signifies snow and green signifies rain, darker colors means heavier snow/rain.

Storm System Timing

The latest model runs show rain and snowfall beginning around town at approximately 11am MST. Initial thoughts were that we were going to get a period of rain followed by a longer period of snowfall that would last until roughly midnight. However, with the cooler temperatures around the metro area, it’s looking like the switch from rain to snowfall should happen sooner rather than later and there’s a good possibility that light snow will be falling in time for the evening rush hour commute. The snow still looks to finish off right around midnight and cloud cover should be clearing out shortly thereafter. I’m so happy to be able to say this… be prepared for very cold temperatures tonight. Most of the front range will be down into the teens and low twenties. Don’t be caught unprepared!

Expected Accumulations

Right now we’re right on par with what we’ve been expecting over the last few days, 1-2″ for the Denver area, 2-4″ for areas south and west along the foothills, and 3-6″ at most mountain locations along the I-70 corridor. There is a possibility for some higher amounts on the high mountain peaks like Echo Mountain, Breckenridge, and Vail, but it isn’t going to effect much down here. Keep in mind that despite the snowfall accumulation predictions, we might not actually see that much laying on the ground because the ground temperature is exceedingly warm from our record breaking temperatures. You will still probably see some accumulation on patio furniture and things of that nature (Don’t tell Kyle Clark), but it won’t be on everything.

You might notice that on the snowfall map there is a lot more snow out east, this is not a glitch. The northeastern plains of Colorado are expecting more snow than the Denver metro area. Make sure that you are prepared for poor driving conditions if you are headed out that way!

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Expected snowfall amounts from this storm

Summary

This storm has already brought us cooler temperatures and they will continue to stay low today and will be downright frightful tonight with lows in the teens and low 20s.  Snowfall beginning soon will bring 1-2″ for most areas and 3-4″ for a lucky few. Other than wet roads, there shouldn’t be much impact from this storm system today. However, tomorrow 3bbf5610b9b464b562e30cfddc491f39morning could yield a few icy conditions after roads have cooled a bit and remained wet overnight. My best advice for this storm is to enjoy it. We’re a week away from Thanksgiving and are FINALLY getting cold weather!

In my opinion, there has been a lot to make just about anyone anxious lately and the holidays are coming up which can make people even more anxious. That’s why I can’t stress this enough. Even if you don’t like winter, take a page out of Linus’ book and go catch snowflakes on your tongue! It keeps you hydrated and is a great way to remind yourself that life isn’t all about nonsensical bickering!

 

Thanks for reading! I hope you enjoyed the forecast.

-Andrew

Five Day Forecast Sept 26th, 2016

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Beaver Run in Breckenridge Sept 25th, 2017     Photo Credit: Megan Schwartz

Another new product today! I’ll be doing brief weekly weather write-ups on Sundays and/or Mondays for those that wanted something to be posted on a more regular basis. These will be known as “Five Day Forecasts” and will actually include an outlook for the foreseeable future past five days as well. Let me know if there’s anything that you’d like to see in them and I’ll do my best to accommodate your request!

It’s definitely cold outside this morning as temperatures hover in the 40s for most of the state and fresh snow that fell over the weekend blankets the highest mountain peaks. We are certainly living up to the Autumn season after the first official day of meteorological Fall occurred last Thursday the 22nd. A brief respite from cooler temperatures will come again this week, but will transition into cooler temperatures this weekend and early next week. However, our temperatures continue to be above the daily averages this year and we won’t see any big cool downs in the foreseeable future.

Next Five Days

Today- Abundant sun will help us see highs in the mid-70s around town today before cooling down to the mid-40s tonight under clear skies.

Tomorrow (Tuesday)- After a day of recovery from cool temperatures on Monday, highs for the Denver Metro area will be in the upper 70s and low 80s with a few stray clouds. Low temperatures at night will reflect the slight warming trend and will be in the low 50s.

Wednesday- Very similar to Tuesday with highs in the upper 70s and low 80s, mostly clear skies, and lows around 50 degrees.

Thursday- A few more clouds will build into the region as our next small weather system begins to arrive in Colorado. Highs will again be in the upper 70s and low 80s and our overnight lows will be in the mid-50s.

Friday- A low pressure system entering the state will make its way to the eastern plains and will bring a small chance of rain and thunderstorms with it. We’ll see an increase in clouds over Thursday and will have highs that are a few degrees cooler in the mid to upper 70s.

 

Extended Forecast

This upcoming weekend we’ll see another cool down similar to the one that we had this past Saturday and Sunday, but with one notable difference. Based off of the current model runs, the next storm system that comes into the state on Thursday will intensify on the eastern plains until it continues on its path on Monday. However, there is indication of a second storm system that will immediately follow the first one! Between these two systems, we could be looking at a few light rainy days from Saturday through Tuesday of next week. One thing is certain, we are beginning to see weather patterns that are indicative of active fall and winter weather rather than the ones that produce our boring summer weather!

 

As always, let me know how I can improve these posts and if you’d like me to cover anything specific.

Thanks for reading!

-Andrew