Well #bots fans, we have to take what we can get. It looks like we will get a lot of heavy rain today (which we need) and then a brief changeover to snow tonight (which we love). It wont amount to much. After that, there are a few chances for light snow events but nothing big on the horizon for central Indiana. Nonetheless, this is powerhouse of a storm and it is affecting the entire country in some way or another. There's an alert in every state except Arizona.
The barometer keep dropping every 30 minutes!
Here is what the National Weather Service in Indianapolis is saying: (Very long an detailed information)
.Forecast Update... Issued at 936 AM EST Fri Jan 12 2024 The forecast remains on track today with only minor adjustments made. Current surface observations show a deepening low pressure system centered near the MO/IL border with a warm front extending east into central Indiana. The first round of rain this morning was associated with the warm front lifting north. Latest radar imagery shows a dry slot across much of central Indiana. Expect this lull in precipitation to be brief as an intense LLJ advects deeper moisture northward during the day. Steady moderate rainfall, possibly heavy at times, will result in widespread rainfall amounts of 1-2 inches. The threat for widespread flooding is low, but localized flooding in low-lying areas is possible. Strong winds are expected today with occasional gusts up to 50 mph. A tightening pressure gradient on the back side of the aforementioned surface low will lead to more widespread gusts up to 55 mph by the early evening hours. && .Short Term...(This afternoon through Saturday) Issued at 936 AM EST Fri Jan 12 2024 Surface analysis early this morning shows deep low pressure over SW MO. A cold front trailed this area of low pressure into eastern OK and eastern TX. A warm front was found from the low, across southern MO and then across KY. Easterly Surface winds were found across Central Indiana, with dew point temps in the upper 20s to around 30. Aloft, water vapor showed a deep trough of low pressure over the Central Plains, resulting in the previously mentioned associated surface low. Showers and storms within the warm sector were found over Arkansas, while lighter showers were found ahead of the warm front over Central IL. GOES16 shows abundant cloud cover ahead of the convection to the southwest streaming toward Indiana. Today... An active weather day will be in store. The strong surface slow is suggested to push northeast toward Indiana today, allowing the warm front to the south to push across Central Indiana. Models suggest a very strong LLJ ahead of the surface low with winds near 50 knots amid this flow across Central Indiana. A strong pressure gradient is also expected today as this possibly historically deep low pressure system pushes across Central Indiana this afternoon. Thus strong gusty winds around 40 mph with isolated higher gusts will be possible this afternoon and tonight. Caveat remains this afternoon as lower clouds arrive if we will be able to mix down some of those higher gusts. For now the Advisory level wind gusts appear to be quite certain, thus will trend toward Wind advisory today. Should it become apparent that an organized area of higher winds, clearing developing (unlikely), or some rogue convection develop (Better chances for that south of Central Indiana), short-lived high wind warnings will be used. Strong isentropic lift is in place today. The GFS 290K surface shows strong upglide with specific humidities up to 4.5 g/kg. Best lift is present during the morning and early afternoon hours as the low to the southwest approaches. HRRR shows two main pushes of rain today. The first arriving near rush hour and the second late this morning and afternoon as the warm front pushes north across the forecast area. Forecast soundings today show a deeply saturated column with pwats near 0.70 inches. Thus confidence for rain today is high. Today`s expected impacts include: Rainy and windy conditions, with brief heavy rain possible. Wind gusts to around 40-45 mph will result in unsecured outdoor items being blown about. Isolated tree limbs being blown down and associated isolated power outages will be possible. Tonight... As we start tonight, the strong surface low will continue to be deepening and found over northern Indiana. Models suggest this low will then push northeast to Lake Huron, deepening all the way. This will continue to keep a strong surface pressure gradient in place across Central Indiana amid cold air advection and cyclonic lower level flow. The cold front associated with the low will push east of Central Indiana by 00Z, resulting in very windy and cold conditions. Also as the low departs the 290K Isentropic surface shows strong downglide and drying. Forecast soundings show dry air arriving aloft, but saturated lower levels due to trapped lower level moisture. Given the cyclonic flow, a few scattered light snow showers will be possible, but confidence is low in this. HRRR shows very little organized development. Thus will keep some mention of snow showers through the evening hours as the low departs. Strongest winds of the day should be during the evening hours. The pressure gradient across the area at that time will be strongest as the low deepens and subsidence ongoing may help some of the higher winds aloft mix downward. The 850mb winds will remain around 40-50 knts through the evening. Thus gusts in that range do not seem out of the question. Again will keep the advisory focused from mid morning through early Saturday morning. Tonight`s expected Impacts include: Windy conditions, with gusts to around 45-50 mph. This will result in unsecured outdoor items being blown about. Isolated tree limbs being blown down and associated isolated power outages will be possible. Snow showers are possible, with blowing snow reducing visibility. && .Long Term...(Saturday through Thursday) Issued at 301 AM EST Fri Jan 12 2024 Saturday and Saturday night... Initially, central Indiana will still be close enough for some influence from the surface low over northern portions of the region Saturday morning. Trends have been pushing in much drier 700-500mb air in behind the low, leading to a quicker end in surface low related snow showers. The upper level low will still linger behind however, creating isolated snow showers and snow flurries once again during the day on Saturday. With mid to low level temperatures plummeting beneath strong CAA, minimal moisture will be needed to squeeze out a tenth or two of snow accumulations. Snow rates dont look to be too high though with lapse rates failing to promote upscale growth within shower activity. As mentioned, mid to low level temperatures will drop steadily throughout Saturday, but surface temperatures will lag slightly until the upper low departs Saturday night. Once the upper low departs, uniform NW flow and diurnal cooling will push surface temperatures from the low 20s Saturday evening, down to the single digits by Sunday morning. Continued modest wind will make temperatures feel even colder with wind chill values below -10 Sunday through Tuesday... This will be a period of very cold temperatures as Arctic high pressure remains in control at the surface. Even with surface high pressure, an upper level disturbance will push through Sunday night. Now, when I say "upper-level", this only means 15000 feet above the surface since the tropopause will be down near 500mb over this stretch. Because of the condensed troposphere, dry surface layers wont be able to deter snowfall much within upper level disturbance. With this in mind, there will be increasing chances for snow, mainly over southern portions of central Indiana Sunday night into Monday morning. The bulk of the forcing looks to remain south of central Indiana, limiting chances to between 15-40% for our area. If snow does fall, snow rates will be very high (15- 20:1), allowing for efficient accumulations even with low QPF. Another upper disturbance could bring more light snow around Monday night into Tuesday morning. Models begin to vary significantly this far out though, with questions still remaining about moisture availability and where the upper level trough will track Highs will be in the single digits above zero to the teens, with lows from around zero into the positive single digits. Temperatures will be influenced by cloud cover timing and any snow that does fall, so these numbers may change. Wind chills will be below zero, with readings down to around -15 at times for portions of the area. Wednesday and beyond... The Arctic high begins to move out mid week, with slight moderation possible as surface winds veer towards southerly. This could allow for highs back into the 20s and even 30s by Thursday. This will be short lived however, with another through passing through late next week, and continued arctic air behind the trough.
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