Pandemic May Be Impacting Forecast Accuracy

Meteorology is not an exact science, like economics, foreign policy and dating. Predicting any future state of the atmosphere depends on how well we can capture fluid dynamics within a weather model, and the accuracy and frequency of data powering that model. Think low-octane vs. high-octane fuel.

Right now we may be using the cheap stuff. The pandemic has impacted the airlines with fewer flights, and that means less upper-air data flowing into the simulations we rely on to have a prayer of getting the forecast right. Couple that with what’s now predicted to be the busiest tropical season in recent memory and you have cause for concern.

Prepare for the worst – hope for the best.

After the coolest start to August since 1993 a warmer front returns for the weekend, with a few rounds of thunder. The best chance of statewide storms: Friday night and early Saturday, again late PM hours Sunday. Highs reach the 80s with a soupy dew point topping 70. Free saunas for everyone!

Pockets of moderate drought linger from Alexandria to Duluth. Cue the storms.


Map credit above: U.S. Drought Monitor.



Ripe for T-storms. An influx of heat and moisture will leave the atmosphere overhead riled up and capable of a T-storm anywhere at anytime – best chance may be Friday night, as a possible squall line forms over the Dakotas and pushes east into Minnesota.


ECMWF: 1″ Rains by Sunday Evening? At least for parts of western, central and southern Minnesota, based on the 12z European run. Considering pockets of moderate drought over west central Minnesota, the rains will be welcome across much of the state. Graphic credit: WeatherBell.









Temperatures Running Above Average Into Next Week. With metro average highs in the low 80s now temperatures are forecast to be about 2-7F warmer than average looking out the next week or so; the best chance of weekend sunshine Saturday afternoon and Sunday morning and midday. Map sequence above: Praedictix and AerisWeather.


A Whiff of Dog Days. When I think of Dog Days of Summer I think of a long streak of 90s in August. We won’t have that anytime soon, but dew points will be close to 70F into next week, with a noticable heat index each afternoon. MSP Meteogram above: WeatherBell.


Hotter Than Average Latter Half of August? We got off to a relatively cool start, but models hint at a warm middle and end of August with a nearly stationary bubble of high pressure over the central USA keep Minnesota and most of the USA warmer than average.

“Extremely Active” 2020 Tropical Season – Colorado State University. Fox News has details: “…The latest outlook from CSU calls for 24 named storms, 12 of which are expected to become hurricanes, and five becoming major hurricanes, which are Category 3 or higher with winds greater than 110 mph. “We have increased our forecast and now call for an extremely active 2020 Atlantic hurricane season,” CSU researchers said on their website. “Sea surface temperatures averaged across the tropical Atlantic are much warmer than normal, and vertical wind shear is well below average...”


NOAA Agrees: Elevated Tropical Risk in 2020. Here’s an excerpt of an update from NOAA: “...A comprehensive measure of the overall hurricane season activity is the Accumulated Cyclone Energy (ACE) index, which measures the combined intensity and duration of all named storms during the season. Based on the ACE projection, combined with the above-average numbers of named storms and hurricanes, the likelihood of an above-normal Atlantic hurricane season has increased to 85%, with only a 10% chance of a near-normal season and a 5% chance of a below-normal season. “This year, we expect more, stronger, and longer-lived storms than average, and our predicted ACE range extends well above NOAA’s threshold for an extremely active season,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center...”


2020: Will We Need Greek Alphabet to Name Storms? Capital Weather Gang weighs in: “…About 95 percent of hurricanes and major hurricanes form from August to October, National Weather Service director Louis Uccellini said during a news conference call. Uccellini said this is one of the most active hurricane outlooks NOAA has ever issued. It would take only 21 named storms before all the names on the Atlantic list, determined ahead of time by the World Meteorological Organization, are exhausted and forecasters would turn to the Greek alphabet. This happened only once before, in 2005, a devastating season that was the most active on record…”

Graphic credit: “The 2020 Atlantic tropical cyclone names selected by the World Meteorological Organization.” (NOAA).


We’re Gonna Need A Bigger Alphabet: Climate Nexus has headlines and links: “The 2020 hurricane season is now expected to be the most active since at least the early 1980s, meteorologists at Colorado State University, a standard bearer for seasonal hurricane predictions, announced Wednesday. The revised estimates predict the 2020 season will see 24 named storms, including 12 total hurricanes and 5 major hurricanes. Each of those predictions are about double that for a normal season, and include storms that have already occurred. 2020, which has already set numerous records for its early activity, still has about 90% of the official season ahead. Even if 2020 sees fewer storms than the new prediction — which is the most dire in CSU’s 37-year history — officials may still run out of letters with which to name storms and be forced to use the Greek alphabet for overflow since the letters Q, U, X, Y and Z are not used. The only other time officials were forced to use the Greek alphabet was 2005 which included five hurricanes (Dennis, Katrina, Rita, Stan and Wilma) so destructive their names have been retired from future use.” (Weather Channel, The Hill, CBS, USA Today, News4JAX, WYFF4, WFLA, WMBF; Climate Signals background: 2020 Atlantic hurricane season)


Three Times More 90-Degree Days Than 2019. Last summer it wouldn’t stop raining, and that kept temperatures considerably cooler. So far in 2020 the MSP metro has experienced 12 days at or above 90 degrees. Source: NOAA and Praedictix.


How the Pandemic Defeated America. If you haven’t yet read Ed Yong’s post at The Atlantic do yourself a favor and read it; here’s an excerpt: “…Many conservationists jump on epidemics as opportunities to ban the wildlife trade or the eating of “bush meat,” an exoticized term for “game,” but few diseases have emerged through either route. Carlson said the biggest factors behind spillovers are land-use change and climate change, both of which are hard to control. Our species has relentlessly expanded into previously wild spaces. Through intensive agriculture, habitat destruction, and rising temperatures, we have uprooted the planet’s animals, forcing them into new and narrower ranges that are on our own doorsteps. Humanity has squeezed the world’s wildlife in a crushing grip—and viruses have come bursting out…”


The Reason Dogs are Terrified of Thunderstorms – and How You Can Help. It makes more sense now, after browsing a post at Mental Floss: “…Many dogs are distressed by unexpected loud noises—a condition known as noise aversion, or noise phobia in more severe cases—and sudden thunderclaps fall into that category. What separates a wailing siren or fireworks show from a thunderstorm in a dog’s mind, however, is that dogs may actually realize a thunderstorm is coming. As National Geographic explains, not only can dogs easily see when the sky gets dark and feel when the wind picks up, but they can also perceive the shift in barometric pressure that occurs before a storm. The anxiety of knowing loud noise is on its way may upset your dog as much as the noise itself...”

Photo credit: Florida Tech.


79 F. high in the Twin Cities on Thursday.

82 F. average high on August 6.

86 F. maximum temperature on August 6, 2019.

August 7, 1968: 7.09 inches of rain falls at Mankato. 1,200 homes are damaged. Highways 169 and 22 are blocked by mudslides.

August 7, 1955: The climate record of George W. Richards of Maple Plain ends. He recorded weather data with lively notations on phenology and weather events. He began taking observations when he was eleven in 1883. He continued to take observations for 72 years, with 66 years as a National Weather Service Cooperator.

August 7. 1896: The final day of a massive heat wave brings highs of 104 to Le Sueur and Mazeppa.

August 7, 1863: A Forest City observer sees what he calls a ‘perfect tornado.’ He noted that it ‘drove principally from west to east and lasted about one half hour.’




FRIDAY: Warmer, few T-storms. Winds: SE 10-20. High: 84

FRIDAY NIGHT: Good chance of T-storms, some may be heavy. Low: 70

SATURDAY: Potentially wet start. Warm sun PM hours. Winds: SW 7-12. High: 86

SUNDAY: Sunny start, more PM T-storms likely. Winds: S 7-12. Wake-up: 71. High: 87

MONDAY: Becoming sunny and less humid. Winds: NW 10-15. Wake-up: 66. High: 81

TUESDAY: Warm sunshine, very nice. Winds: SW 8-13. Wake-up: 62. High: 83

WEDNESDAY: Hazy sun, isolated T-storm? Winds: S 8-13. Wake-up: 64. High: 85

THURSDAY: Sticky sunshine, few pop-up storms. Winds: S 8-13. Wake-up: 68. High: 86


Climate Stories…

Worst-Case Scenario for Global Warming Tracks Closely with Actual Emissions. InsideClimate News reports: “...But a new study published Monday in the Proceedings of the National Academy of Sciences argues that the high-end projection for greenhouse gas concentrations is still the most realistic for planning purposes through at least 2050, because it comes closest to capturing the effects “of both historical emissions and anticipated outcomes of current global climate policies, tracking within 1 percent of actual emissions.” The scenarios, called Representative Concentration Pathways (RCPs), roughly show how much warmer the world will be by 2100, depending on how much more fossil fuel is burned, and how the climate responds. The best-case scenario (RCP 2.6) is the basis for the Paris climate agreement and would lead to warming of about 3.2 degrees Fahrenheit (1.8 Celsius) by 2100…”

Image credit: Scott Kelly, NASA ISS.


This is Inequity at the Boiling Point. Here’s an excerpt from a story at The New York Times (paywall): “…Nearly everywhere around the world, heat waves are more frequent and longer lasting than they were 70 years ago. But a hotter planet does not hurt equally. If you’re poor and marginalized, you’re likely to be much more vulnerable to extreme heat. You might be unable to afford an air-conditioner, and you might not even have electricity when you need it. You may have no choice but to work outdoors under a sun so blistering that first your knees feel weak and then delirium sets in. Or the heat might bring a drought so punishing that, no matter how hard you work under the sun, your corn withers and your children turn to you in hunger…”

Map credit: The New York Times | Source: Climate Impact Lab.


CLIMATE IMPACTS: Headlines and links courtesy of Climate Nexus: “Scientists tell Congress neglecting climate change costs more than addressing it (Politico Pro $), US could avoid 4.5M early deaths by fighting climate change, study finds (The Hill), flooding could occur daily in Sydney by the end of this century because of climate change.” (The Guardian)


Bill Gates: Pandemic’s Misery Will “Happen Regularly” if Climate Change is Not Stopped. Fox News (?) has the post: “…If you want to understand the kind of damage that climate change will inflict, look at COVID-19 and spread the pain out over a much longer period of time,” the Microsoft co-founder wrote on his blog Tuesday. “The loss of life and economic misery caused by this pandemic are on par with what will happen regularly if we do not eliminate the world’s carbon emissions.” Gates estimated that the death toll from climate change would match that of the pandemic by 2060, and exceed it fivefold by 2100. The economic impact of climate change over the next two decades, he added, could be “as bad as having a COVID-sized pandemic every ten years…”

File image credit: NASA.



Arctic Sea Ice. Call me crazy but I notice a trend over the decades. Credit: “Latest PIOMAS (model; Zhang and Rothrock, 2003) sea ice volume (SIV) across the Arctic (updated for July 2020).” Zachary Labe.