Frosts hit Brazil's cane, coffee and orange crops, says weather expert
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Started by metmike - July 22, 2021, 1:22 a.m.

SAO PAULO, July 20 (Reuters) - Frosts hit crops including sugar cane, coffee and orange in the center-south region of Brazil on Tuesday, according to a report by a Rural Clima meteorologist.

Marco Antonio dos Santos, a meteorologist who is a partner and director at the weather service consultancy, said earlier on Tuesday that he had received multiple videos showing frosts, but noted it was too early to determine the exact damage to these crops. Temperatures should rise starting on Wednesday as a cold front moves away, he said.

Coffee brokers said this frost was stronger than the last one, hitting farms in Minas Gerais state, the top producer.

Frosts were documented as far as the south of Goiás state, in the heart of Brazil's farm country, Santos said, referring to the center-west region, where average temperatures tend to be higher than in southern Brazil.

Santos also predicted frosts "as bad" as Tuesday's could return at the end of the month in the center-south region, where some farmers have not yet finished harvesting their second corn crop. 

Starting on Saturday, a new cold front will hit Brazil's southernmost state of Rio Grande do Sul, Santos said.

That system is expected to move northward and bring showers to important agricultural regions, reaching as far north as the state of São Paulo, he said. With rains persisting in the first half of August, winter crops like wheat in the south of Brazil will benefit, he said.

Brazil, the world's biggest soybean producer, will start planting its next soybean crop around September in the center-western states like Mato Grosso.

By then, Brazil should have returned to "a normal" rain regime, Santos added.

In the first half of 2021, farmers faced the worst drought in 91 years, damaging part of their second corn crop and reducing Brazil's export prospects. 

So far, models indicate a normal rain pattern for the second half of September in the center-west region. In October, however, a short dry spell is likely to be driven by a mild La Niña, Santos noted, referring to the same region.

metmike: Pinpointing the length of a dry spell in October(to short duration) in a weather forecast made in July???

The skill/performance for such a forecast, to my knowledge is extremely low/almost non existent.

By metmike - July 22, 2021, 1:27 a.m.
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Freak Brazil frost hits heart of coffee belt, damaging crops

SAO PAULO/NEW YORK, July 21 (Reuters) - An unusual cold snap, with temperatures dropping to freezing levels in a matter of minutes, delivered a blow to the heart of Brazil's coffee belt, damaging trees and harming prospects for next year's crop, farmers said on Wednesday.

Agricultural products across the western hemisphere have been beset by unusually bad weather - be it floods or extreme drought - all season. Brazil is the world's largest coffee producer, as its climate is most conducive for production of the beans. Coffee prices surged nearly 13% in response to the  frosts to a 6-1/2-year high.

The sudden frost happened in the morning of July 20. According to Brazil's National Meteorology Institute (Inmet) the minimum temperature in Minas Gerais was -1.2 Celsius (29 Fahrenheit). Farmers, brokers and analysts were assessing their crops on Wednesday after reports that the cold snap was much stronger than expected.

"I've never seen something like that. We knew it would be cold, we were monitoring, but temperatures suddenly went several degrees down when it was already early morning," said Mario Alvarenga, a coffee producer with two farms in Minas Gerais, Brazil's largest producing state.

Farmers shared pictures of their crops, where large black areas were visible in places where they should see dark green spots marking coffee trees.

"I will probably have to take out some 80,000 trees, they are burned all the way to the bottom," said Airton Gonçalves, who farms 100 hectares (247.11 acres) of coffee in Patrocinio, in the Cerrado region of Minas Gerais.

"I was going to the farm yesterday and a sensor in the truck started to alert me about ice on the road. I thought the system had gone crazy. But when I got to the farm, it was covered in ice, the roofs, the crops."

Gonçalves estimates his production in 2022 will fall to around 1,500 bags from the usual 5,500 bags.

Ana Carolina Alves Gomes, a coffee analyst at Minas Gerais agriculture federation Faemg, said frosts were reported also in the South of Minas Gerais and in the Mogiana area in Sao Paulo state.

"Only time will tell how much will be lost. We already had a small crop this year," she said.

Cooxupe, the world's largest coffee co-op and Brazil's largest exporter, said its agronomists were visiting farms on Wednesday to better assess potential damages. It plans to release a report in coming days.

Broker Thiago Cazarini, who operates in Varginha, South Minas, said that preliminary estimates from exporters and agronomists point to a potential reduction of 1 to 2 million bags in next year's crop.

"For a clearer view, proper time is needed. Next week it will be more accurate," he said.

metmike: The weather pattern did not look extremely cold enough to do ws a huge surprise!

By metmike - July 22, 2021, 10:15 a.m.
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I think I know now why this air mass turned out MUCH colder than what the models and forecasters predicted. The widespread drought and extremely dry soils/surface, prevented the cold air mass from moderating when headed north and in fact, may have dried it out even more tracking over the very dry ground, so the dew points were extremely low and with clear skies and no winds, this allowed temperatures to plunge down to the very low dew points with an extreme radiation frost.

See how dry its been in South America the last 6 months.......because of the La Nina/cool water temperatures in the Eastern tropical Pacific. We need some global warming and an El Nino(warmer water temps) to break this drought(and the one in the West/N.Plains of the US)


                June 2021 global temps: -0.01 deg. C vs 30 year average            

                            Started by metmike - July 3, 2021, 5:44 p.m.    

By metmike - July 22, 2021, 10:23 a.m.
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By metmike - July 22, 2021, 10:26 a.m.
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Monitoring for the risk of frost and freezing temperatures

The dewpoint temperature is defined as the temperature at which water vapor in the air will begin to condense into dew, fog, or clouds if the air is cooled. A directly-related term, relative humidity, is defined as the ratio of the amount of water vapor that is actually in the air divided by the amount that could be potentially held by the air at that temperature. When the air temperature falls to the dewpoint, the air is said to be saturated, as it cannot hold any more water vapor. Any excess moisture is condensed out into liquid (dew) or ice (frost).

By Jim_M - July 22, 2021, 10:35 a.m.
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With already diminished output expectations because of all the dryness and also being an off year, this could really stick a fork in the coffee crop.

By metmike - July 22, 2021, 10:44 a.m.
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                                                   METEOROLOGIST JEFF HABY

Dew forms when the temperature becomes equal to the dewpoint. This often happens first at ground level for two reasons. First, longwave emission causes the earth's surface to cool at night. Condensation requires the  temperature to decrease to the dewpoint. Second, the soil is often the moisture source for the dew. Warm and  moist soils will help with the formation of dew as the soil cools overnight.

The cooling of warm and moist soil during the night will cause condensation especially on clear nights. Clear skies allow for the maximum release of longwave radiation to space. Cloudy skies will reflect and absorb while re-emitting longwave radiation back to the surface and that prevents as much cooling from occurring. Light wind prevents the mixing of air right at the surface with drier air aloft. Heavier dew will tend to occur when the wind is light as opposed to when  the wind is  strong. Especially when soils are moist, the moisture concentration will be higher near the earth's surface than higher above the earth's surface. As the air with higher moisture concentration cools, this air will produce condensation first.

Soil moisture is EXTREMELY critical to producing dew (especially heavy dew). Dry regions that have not received rain in over a week or two are much less likely to have morning dew (especially a heavy dew).

metmike: This was a very unusual case where the calm winds and clear skies(and long night)  were mega optimal for radiation cooling and  allowed temperatures to PLUNGE much greater than usual on top of extremely dry soils, so the temperatures near the ground were able to get all the way down to the very low dew(frost) point.

 When temperatures drop below freezing and the temperature reaches the dew or frost point, the ice on the ground is termed frost or frozen dew. "Frost" can form in two ways: Either by deposition or freezing. Depositional frost is also known as white frost or hoar frost. It occurs when the dewpoint (now called the frost point) is below freezing. When this frost forms the water vapor goes directly to the solid state. Depositional frost covers the vegetation, cars, etc. with ice crystal patterns (treelike branching pattern). If the depositional frost is thick enough, it resembles a light snowfall.

Frost that forms due to the freezing of liquid water is best referred to as frozen dew. Initially, both the dewpoint and temperature are above freezing when dew forms. Longwave radiational cooling gradually lowers the temperature to at or below freezing during the night. Cold air advection can also do the trick (e.g. Cold front moving through in the middle of the night after dew has formed). Once the temperature falls to freezing, the condensed dew droplets freeze. Frozen dew looks different from white frost. Frozen dew does not have the crystal patterns of white frost. White frost tends to looks whiter while frozen dew tends to look slicker and more difficult to see.


Q: Can frost occur at temperatures above 32°F?

A1: No, frost is defined as a layer of ice that forms on surfaces that are at or below 32°F. Sometimes frost can occur on your lawn overnight, even though your thermometer may never have dropped to the freezing mark. This is because cold air on clear, calm nights sinks to ground level. Temperatures at the ground can be lower than the temperature only a few feet higher where your thermometer may be located.

 Since official weather measurements are taken in an instrument shelter four to five feet above the ground, frost can form even when the official temperature is above freezing.

A2: The ground, or any surface, must be at or below 32 for frost to form.

 However, if your thermometer was just a few feet above the ground, it may not have given an accurate reading for frost. A thermometer shows the temperature where the thermometer is located.

 Because cool air sinks and the ground can quickly cool, the ground temperature on clear, still nights is invariably lower than the temperature only a few feet higher. This is especially common in the fall and winter when nights are long, which allows extra time for cooling. Thus, frost can form even when a thermometer gives a reading in the upper 30s.

 Since official weather measurements are taken in an instrument shelter four to five feet above the ground, frost can form even when the official temperature is above freezing. (Related: measuring weather).

 Additionally, frost will only form if the ground temperature matches the dew point. (Related: understanding humidity).

"The dew point is the temperature at which the air is saturated with respect to water vapor over a liquid surface. When the temperature is equal to the dewpoint then the relative humidity is 100%. The common ways for the relative humidity to be 100% is to 1) cool the air to the dewpoint"

metmike: or frost point. In this case, the dew/frost points plunged really low because the ground was so dry.


"Two surfaces that are good at collecting dew or frost are vegetation and metal. Vegetation has moisture evapotranspiring from its surface. This causes the dewpoint to be higher over vegetated surfaces and thus dew or frost will form on them first."

By Jim_M - July 22, 2021, 11:59 a.m.
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Good stuff!  Thanks for posting Mike.  

By tjc - July 22, 2021, 11:59 a.m.
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 Thank you, MetMike

  I was fortunate to close out a long position near yesterday's close.  A very profittable trade.

  I was UNfortunate to close out a long position yesterday--so sad, as profits would have doubled.

  VERY hard to re-enter as KC has rallied parrabolically.  

  This WEATHER market in coffee makes the U.S. grain drought look pale.  This freeze has yet to be properly assessed, but a change in weather for next midweek could see a 40 buck drop.  If cold confirmed for next week, look for 220ish.

  Again, very difficult to trade.

  MetMike--this move reminds me of your hourly calls in NG during the Karina days--very profitable back then!!

By Jim_M - July 22, 2021, 12:15 p.m.
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There is no daily limit on coffee?  

By metmike - July 22, 2021, 12:40 p.m.
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Thanks tjc and congrats on your nice profits.

I know how that goes..........getting out too soon. Taking a profit on a long position then, hoping the market will go down right then so we/you/me feel really great about the place that your if we can pick the exact top.

When it continues higher, watching it constantly and calculating constantly how much money we would  have made if..............WE HAD ONLY STAYED IN!

I was caught totally off guard by this freeze. For one thing, I was in Detroit earlier this month and didn't have time to look at coffee weather but it apparently would not have looked as strong as it turned out to be because of the factors I analyzed in detail above.

I could have used those factors in the US because I have enough data and understand the terrain. In Brazil, I don't have nearly as much data and the terrain in coffee land is really tricky with regards to the role that it played here.

It's not just a bunch of flat ground like we have in the Midwest.

The elevations vary and are very prone to cold air drainage, hugging the ground in a situation like this. That appears to be what happened because of several unique factors that almost never happen simultaneous and would be impossible to see without having all the information needed to predict it..............and also, a gifted ability to see something almost nobody else, including the models saw coming. 

In that past, a freeze/frost this damaging would have been  dialed into the price of KC/ risk premium WELL BEFORE it happened because the weather pattern causing it would have been obvious.

This was the worst freeze since 1994, when there were 2 of them earlier in the Summer.

27 years ago and the pattern for that one showed it coming ahead of time.

Although back then, we didn't have models that went out for more than a couple of days, so the market couldn't see that one coming way out ahead of time either.........but it was really obvious when we got within the 48 hour time frame of the reliable models.

The same models today in 1994 and the market would have seen those freezes  coming over a week before it happened.

The synoptic weather pattern was much more powerful then, loaded with much colder air coming thru Argentina than this one appeared to have.

The position of the surface high then was more favorable.

The freezes previous to 1994 were often caused by Coffee being farther south........farther from the equator. 

By WxFollower - July 22, 2021, 1:55 p.m.
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 I hadn't been following KC recently and was shocked to read this about frost. I was able to just now look back at my WSJ news feed for KC wx and I found absolutely nothing indicative of an incoming frost threat vs the norm of cold and a threat being mentioned!!

 Tue 7/20: highly unremarkable! Wed 7/21 is about the same

07/20 01:30a CST  DJ Brazil Coffee Weather - Jul 20 
Brazil Coffee/Citrus/Cane...  
  Mostly dry. Temperatures above normal north and falling below normal south.  
Coffee/Citrus/Cane Forecast....  
  Mostly dry through Friday. Temperatures above normal north and below normal  
south through Wednesday, near to above normal Thursday-Friday.  

 I just saw that this was put out yeterday:

07/21 10:23a CST  DJ Coffee Prices Hit Highest Since 2018 -- Market Talk 
     1123 ET - Coffee futures trading on the Intercontinental Exchange are at 
their highest levels since January 2018, with the most-active contract up 4.7% 
to $1.7455 per pound Wednesday. Coffee futures have gotten their lift from 
supply constraints in Brazil due to weather. "Above all, it has been the risk 
of frost in Brazil that has repeatedly fueled price fantasies since June," says 
Commerzbank. "Key growing areas had been spared frost in June, but now 
temperatures as low as -4degC were reported yesterday in the southern part of 
Minas Gerais, the most important Arabica growing state." (; 
  (END) Dow Jones Newswires 

  I'm now looking at other sources of stories and will post if I get time.

By metmike - July 22, 2021, 5:51 p.m.
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tjc was on this one beforehand for sure......much more than I was. 

 He actually sent me an email on Tuesday pm, when I was away from my computer,  so I know that he was on it then. 

By metmike - July 22, 2021, 5:59 p.m.
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For those that missed some phenomenal, money making  posting by WxFollower last year in the coffee market, it's well worth the read below:


                            52 responses |              

                Started by rockitck - July 22, 2020, 8:48 p.m.   

                Coffee 10/29/20-11/9/20            

                            55 responses |           

                Started by WxFollower - Oct. 29, 2020, 8:32 p.m. 


                Coffee 11/10/20-11/27/20            

                            41 responses |              

                Started by WxFollower - Nov. 10, 2020, 2:07 a.m.    

By metmike - July 22, 2021, 6:07 p.m.
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The price charts below are updated.

I remember coffee trading around 50c for awhile back in the early 90's...........before  the massive freeze events in 1994....which soared to $3 if I remember right. I almost never traded options in my life but sold some $3 coffee calls on the recommendation of Craig Solberg at Weather Trades........collected the entire premium.

Coffee charts going back 10 years:

     2 years


5 Years below



Coffee, 5 year chart below.....close to the 2014 drought highs!


 Coffee 10 years below

Drought in Brazil in 2014 caused a spike

Drought in Brazil and bad weather globally in 2010 caused the 2011 spike

Current price near the 2014 highs.





By metmike - July 22, 2021, 6:07 p.m.
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As you probably know, the dry season for coffee country in Brazil often continues well into September. For those that are not aware of where the main growing areas are:

This is where they grow coffee in Brazil.....the worlds biggest producer.

The higher the number below, the greater the production. 1=highest.    



By metmike - July 22, 2021, 6:08 p.m.
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Looking at the global picture of coffee production below.

Brazil matters the most!


By metmike - July 22, 2021, 6:12 p.m.
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Here is a list of historic weather events from frost/freezes and droughts thru 2000 for Brazil.

We had a couple of major droughts after that though.......2014 was the big one but dryness that persisted into Oct 2020 had some impact late last year. 

The coffee growing region shifted much closer to the equator around 3 decades ago to lessen the risk of cold and since then, mainly the 1994 freezes did major damage.  Global warming has also helped too. 

This 2021 freeze was definitely the most damaging since the 1994 freeze events.


BodyDate Posted & Author

 Coffee Frost and                       Drought History

DateSeverity (Damage)Coffee Frost or Drought
1902 (Late July/early August)DevastatingF*
1918 (June 24-26)SevereF*
1942 (Late June/early July)SevereF*
1953 (July 4-5)SevereF*
1955 (July 30-August 1)Severeslight F
1962 (July 25-26)MinorF*
1963 (August 5-6)ModerateF and D
1966 (August 6)Severeslight F
1967 (June 8)MinorF*
1969 (July 9-10)ModerateF*
1972 (July 8-9)ModerateF*
1975 (July 17-19)Very SevereF*
1978 (August 13-16)ModerateF*
1979 (June 1)ModerateF*
1981 (July 20-22)SevereF*
1984 (August 25)MinorF*
1985 (August-November)MinorD
1994 (June 25-26 and July 9-10)Severe/Very SevereF and D
1999 (August to November)Severe (40% crop lost)
2000 (July 17)Moderate (est)F*

* In most cases frost or drought was not                    indicated by the source.  Although only F is written in                    these cases it is likely a combination of the two forces                    that caused a devastating coffee crop.


By Jim_M - July 26, 2021, 10:54 a.m.
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Apparently there is another cold weather event for the coffee region in Brazil this week.  The estimates I read are that last weeks frost already hit 11% of the total planted coffee area.  Gonna be jumpy!  

By mcfarm - July 26, 2021, 4:01 p.m.
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By metmike - July 27, 2021, 7:44 a.m.
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Thanks mcfarm,

Not coldest in a century but coldest THIS century that started in the year 2000.

This will not be as cold as 1994.

The set up is not nearly as ideal with the position of the surface high like 1994 but it’s plenty cold enough for a major freeze later this week.

My son is out of the ICU so I may have more time to analyze and post now.

By Jim_M - July 27, 2021, 9:36 a.m.
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Looks like they about doubled the margin for coffee

By Jim_M - July 27, 2021, 11:17 a.m.
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Glad to hear your son is improving Mike.  

By metmike - July 27, 2021, 12:18 p.m.
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Thanks Jim!

KC prices have come too far for a high confidence low risk weather trade here.

There is massive risk premium in the market right now that assumes X amount of additional damage

from this next freeze as well as Y amount of damage from the last freeze.

If a weather model suddenly came out much colder or much less cold, that might be something but there could also be a market shaking report from some reliable local authority to tell us that the Y amount of damae from the surprise freeze earlier this month is MUCH worse or MUCH less than thought and coffee could be 10c higher or lower in a minute.

I also don't have the same extensive array of weather products for South America that lack European model for North America.

By metmike - July 28, 2021, 1:04 a.m.
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By Jim_M - July 28, 2021, 2:14 a.m.
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I’ve made some nice money in the last 3 weeks in coffee, but I close my position at the end of the day.  If I miss some big over night jump, so be it.  As you say, a little change in the weather forecast over night and a trader would get walloped.

By metmike - July 28, 2021, 6:12 p.m.
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So what are you looking for in your next coffee trade Jim?

By Jim_M - July 29, 2021, 10:29 a.m.
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I agree with your statement that coffee has gone too far too fast.  There is a gap down around the 180 range that I think will be filled sooner than later.  This is definitely a weather trade at the moment.  As time goes on and supplies tighten, then a longer term trade might be in order.  For now, I have hit a couple nice short term trades and am sitting on my profits and watching.  

By metmike - July 29, 2021, 10:56 p.m.
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Coffee, cane and orange crops at risk as temperatures plunge in Brazil

metmike: Obviously, the market felt less threatened by frost today, with the coldest morning being Friday morning.

As I've been thinking the position of the center of the surface high is not as optimal for this to be as cold as the 1994 freezes. 

There's a pretty good extension of surface high pressure..........north of the center but the center of the surface high is several hundred miles farther south(in extreme southeast Brazil) than where it would maximize damage(several hundred miles farther north).

By metmike - July 29, 2021, 11 p.m.
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Downstream Amplification: A Possible Precursor to Major Freeze Events over Southeastern Brazil          

metmike: Note how much farther north the surface high was in 1994.

Fig. 1.

By WxFollower - July 30, 2021, 12:10 a.m.
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Hey Mike,

 Am I correct in assuming that the earlier freeze wasn't expected/was a less than ideal setup, also? How far north did the center of the high go and how cold was it in relation to this one? TIA

By metmike - July 30, 2021, 12:47 a.m.
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Great question Larry!

I really don't know. If you or anybody can find a surface weather map with pressure contours for that event please post it. 

By Jim_M - July 30, 2021, 11:39 a.m.
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Nice washout in coffee today.  It's almost closed that gap around 180 as of this post.  

By metmike - Aug. 2, 2021, 8:40 p.m.
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Arabica Coffee Closes at a 1-1/2 Week Low on Reduced Brazil Frost Risks

Coffee prices on Monday closed sharply lower, with arabica coffee falling to a 1-1/2 week low and robusta dropping to a 2-1/2 week low.  Reduced frost concerns in Brazil weighed on arabica Monday after Maxar said warmer-than-normal temperatures are expected for Minas Gerais over the next two weeks and that any additional frost risks have been pushed back toward the end of this month.

Ample rain in Brazil over the past week was another negative for coffee prices after Somar Meteorologia on Monday said that there was 8.7 mm of rain last week, or 229% of the historical average, in the Brazilian state of Minas Gerais, the country's largest arabica-producing region.  

Arabica coffee last Monday soared to a 6-3/4 year nearest-futures high on concern that the twin risks of drought and frost could decimate Brazil's coffee crops.  Coffee trees in Brazil were already weakened by drought and then pummeled by two frosts in less than a month.   Marex today predicts that Brazil 2022/23 arabica coffee production will fall -17% y/y to as low as 42.7 mln bags due to frost and drought damage.  Brazil accounts for 40% of the world's total coffee production.

Rural Clima said that recent damage to coffee trees from frost in Minas Gerais was "very significant" after parts of South Minas Gerais saw the coldest temperatures in 27 years.  Frost may burn leaves and branches on trees and curb the outlook for Brazil's 2022 crop, which is significant because coffee trees are on a two-year cycle and are set to produce more next season.  According to Ecom Research, crop losses for next year's Brazil coffee harvest may range from 4.05 mln bags to 5.2 mln bags.  Ecom's original forecast for Brazil's 2022/23 arabica crop was 48 mln bags, so the estimated losses would represent about 8% to 11% of the total crop.

Coffee prices have recently seen strength on a lack of rain in Brazil.  According to Rural Clima, current soil moisture in Minas Gerais is only around 20%, well below the 60% needed for coffee crop development.  Brazil is in the midst of its worst drought in nearly 100 years.