News
04/24/2023, 5:51 am EDT

AG Climate Research: Projecting May 5-7 Snow Cover Dissipation Dates for Northern Plains/Upper Midwest

The late April 2023 snow cover across the northern Great Plains and Upper Midwest is rare but not unprecedented. Since 1998 (when satellite snow cover is easily attainable) late April significant snow cover across the northern Great Plains and Upper Midwest occurred in 2013, 2017, and 2022.
04/11/2023, 9:11 am EDT

Great Plains Drought Resiliency Redeveloping?

The Great Plains Drought Report: Drought resiliency developing. Discussion: From North Dakota to Kansas, 91% of that stretch was in drought at the beginning of the year. That number lowers to 77% in early April. In the Oklahoma to Texas stretch, 68% of that region was in drought on the 1st of January lowering to 52% in early April. So…aerial coverage of drought has lowered through Q1/2023. However, intense D3/D4 drought remains prominent in Texas, Oklahoma, Kansas, and Nebraska. The precipitation outlooks indicate worsening conditions are possible over the next 6 weeks. Fig. 1: The area of drought concern based on shallow soil moisture deficit extends across the central and western Great Plains. Fig. 2: Deep layer soil moisture deficits often foreshadow where drought will worsen due to the long-term climate implications producing this regime. The target area is the western Great Plains. Fig. 3: The meteorological spring of 2023 (so far) precipitation bias which indicates dryness is persistent across the core of the drought area. Please note that medium range forecast models have been too wet in this zone during the past 30 days. Fig. 4-6: Lack of rain and anomalous warmth can dry soils quickly. However, above normal wind speed also accelerates drying soils as indicated for northwest Texas to Iowa for much of the next 15 days. Fig. 7: Significant rain in the central/south Great Plains is reliably generated by phase_2 of the Madden Julian oscillation during APR/MAY/JUN. Fig. 8: The MJO 15-day forecast indicates a transition across the tropical Pacific (phase_6/phase_7) is indicated. The 15-day history plot (orange) indicates any future visit to desired phase_2 is short-lived.          Fig. 9: The GFS ENS MAXRES 15-day precipitation anomaly forecast indicates mostly dry conditions for the Great Plains drought zone. Fig. 10: The ECMWF week 1-4 precipitation bias is dry across the Mid-south States with the wet anomaly in the Gulf region. This forecast leaves the Great Plains drought area susceptible to worsening conditions. Fig. 11: The ECMWF week 5-6 precipitation bias is dry across most of the Great Plains although a small region of wet weather is projected in the Mid-south States. This forecast is also supportive of worsening drought in the central/western Great Plains.  
03/26/2023, 9:20 am EDT

AG Market Research: Projecting snow cover dissipation North-central/Upper Midwest U.S.

Executive summary: Snow cover is above normal across the North-central/Upper Midwest U.S. and the outlook is for the attendant cold to continue well into the spring season. Additional heavy snowfall is not expected therefore most of the snow cover will erode during April. Historically, snow cover across North Dakota and Minnesota ranges from 10-20% based on the 20-year climatology for early May. The climatological risk is appropriate for both states in 2023 given current conditions and the weather pattern projection into early May. Discussion: Snow cover is above normal across much of the West and North U.S. during late March (Fig. 1). Helping to sustain the snow cover is a locked-in upper-level low-pressure trough across the West U.S. (Fig. 2), characteristic of a negative Pacific North America (-PNA) pattern, which has recently expanded across the North-central U.S. Snow depth across the North-central/Upper Midwest U.S. ranges from bare ground across the lower northwestern Great Plains to 2 feet along the eastern ND/SD state line through North-central MN and into the northwest Great Lakes where higher amount is observed (Fig. 3). The snow cover remains significant to U.S. temperature bias through the next 15 days as GFS maintains cold signatures that sustain snow cover in the West and North U.S. (Fig. 4). While the cold across snow cover is not likely to change much through the first third of April, a look at the most likely upper air pattern for mid-to-late April and early May by ECMWF is required. The week 4-6 forecast indicates a susceptibility for low pressure troughing to elongate from the Southwest U.S. to the East-central States (Fig. 5). In this scenario, Pacific westerlies required to scour away the cold and snow across the northeast Great Plains/Upper Midwest and Northern Rockies is less likely as wind has a tendency to be easterly. Consequently, the cold bias remains, possibly stronger than indicated by the model (Fig. 6). Additionally, this is a wet scenario for the Mid-south U.S. (Fig. 7) eroding the eastern portion of the current Central U.S. drought. Based on current snow cover, the operational 15-day forecast which (mostly) maintains the cold bias but without major additional snowstorms, and extended-range outlook provided by ECMWF, an estimate at snow dissipation timeframes for the North-central/Upper Midwest U.S. is provided. Looking back 20 years to establish a precedent for early May snow cover across parts of the North-central/Upper Midwest U.S. indicates 2019 as the last time the snow cover issue was present. In 2019 the snow cover was gone by May 10th. Snow cover was just east of crop areas in Minnesota in early May of 2017 melting shortly thereafter. In 2014, deep snow cover was present just north of Minnesota crop areas lasting into late May before dissipating. A similar and more widespread snow cover was present in 2013, along and north of the U.S./Canada border. All of North Dakota was covered with snow during early May of 2011 dissipating by May 10th. Northern Minnesota crop areas observed snow cover during early May of 2008. Historically, early May snow cover is possible, but the 20-year climatology suggests that the risk in North Dakota is 10% and in Minnesota 20% with no risk farther south. The historical precedent for no snow cover by early May is strong. However, the expected weather pattern cited does provide optimal risk for lingering snow cover. The outlook is for slight risk of snow cover biased to the eastern half of North Dakota in early May dissipating shortly thereafter. The risk of snow cover presence across central and northern Minnesota is 20% during early May, also melting shortly thereafter. To increase the risk, additional snowstorms are required and although the temperature forecast is on the cold side, major snowfall events are not seen in the current outlook. Fig. 1-2: Rutgers Snow Laboratory analysis of snow cover anomalies for March 25, 2023, across the northern hemisphere and the 30-day 500 MB anomaly analysis across the northern hemisphere by NCDC/PSD. Fig. 3: Snow depth analysis across the U.S. provided by NOAA. Fig. 4-5: The GFS 15-day North America temperature anomaly forecast and ECMWF week 4-6 prevailing upper air pattern outlook. Fig. 6-7: ECMWF week 4-6 temperature and precipitation anomaly outlook for North America. State 5-May 15-May 25-May 31-May MN 20% chance snow on the ground Northwest MN. Snow cover gone.     MT Snow cover gone.       ND 10% chance snow on the ground most of state. Snow cover gone.     SD Snow cover is gone.       WY Snow cover is gone (northeast WY).       Table 1: Snow cover presence projected over full RMA crop revenue insurance timescales for spring wheat final plant dates. State 5-May 15-May 25-May 31-May MN Northern half of MN 20% chance snow on the ground. Snow cover is gone.     ND 10% chance snow on the ground most of state. Snow cover is gone.     SD Snow cover is gone.       Tables 2: Snow cover presence projected over full RMA crop revenue insurance timescales for corn final plant dates. State 5-May 15-May 25-May 31-May MN Northern half of MN 20% chance snow on the ground. Snow cover is gone.     ND 10% chance snow on the ground eastern ND. Snow cover is gone.     SD Snow cover is gone.       Tables 3: Snow cover presence projected over full RMA crop revenue insurance timescales for soybean final plant dates.  
03/15/2023, 12:56 pm EDT

Strong El Nino/Positive Phase Indian Ocean Dipole Correlate to Europe Summer Drought

Executive summary: The combination of an impressive warm ENSO and positive Indian Ocean dipole is forecast by the Australia Bureau of Meteorology for JUL/AUG/SEP 2023. If so, analogs emphasize a strong upper ridge across Europe returning the dry/hot regime observed last year biased slightly farther eastward. The El Nino/+IOD pattern favors an upper-level anomalous warmth and dry climate-inducing regime over the North-central U.S. to possibly the Northwest States during this time. Discussion: The latest Australia Bureau of Meteorology (ABOM) ENSO and Indian Ocean Dipole (IOD) forecasts feature sharp positive phase for mid-year. El Nino onset is in APR/MAY and strong El Nino emerges by JUL/AUG (Fig. 1). At the same time, an impressive +IOD also emerges (Fig. 2). Analog years (since 1980) producing El Nino/+IOD regimes are 1982, 1983, 1997, 2006, 2012, and 2015 (during JUL/AUG/SEP). The 500 MB anomaly pattern for the analog years combined during JUL/AUG/SEP produces a RED FLAG upper ridge/drought risk for Europe (Fig. 3). Using the modern-day analogs (2006, 2012, and 2015) the upper ridge is centered on Ukraine (Fig. 4). In North America, the analogs render a strong upper ridge over Central Canada to the North-central U.S. in-between upper troughs on both coasts (Fig. 5). This scenario could produce a North-central/Central U.S. drought concern. The modern-day analogs, the upper ridge exposure to the U.S. is across the Northwest while an upper trough occupies the eastern Ohio Valley (Fig. 6). Elsewhere, an upper trough is produced by the analogs for much of China suppressing drought risk. In the southern hemisphere, a strong upper ridge resides just south of Australia while upper troughs emerge either side of Argentina replacing the persistent ridge patterns in this location during much of the past decade. Fig. 1: Australia Bureau of Meteorology ENSO forecast. Fig. 2: Australia Bureau of Meteorology Indian Ocean dipole forecast. Fig. 3-4: El Nino and positive Indian Ocean dipole analog years since 1980 and the upper air pattern generated over Europe (left). Analog years since 2000 (right). Fig. 5-6: El Nino and positive Indian Ocean dipole analog years since 1980 and the upper air pattern generated over North America (left). Analog years since 2000 (right).