diff --git a/.gitignore b/.gitignore
index a443bd4..4df8d49 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 /target
 
-input
-rv.png
+*.png
+config.toml
+data/
diff --git a/Cargo.lock b/Cargo.lock
index 023a266..62e817c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -8,6 +8,15 @@ version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "512761e0bb2578dd7380c6baaa0f4ce03e84f95e960231d1dec8bf4d7d6e2627"
 
+[[package]]
+name = "approx"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cab112f0a86d568ea0e627cc1d6be74a1e9cd55214684db5561995f6dad897c6"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.4.0"
@@ -32,6 +41,12 @@ version = "1.23.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9134a6ef01ce4b366b50689c94f82c14bc72bc5d0386829828a2e2752ef7958c"
 
+[[package]]
+name = "byteorder"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
+
 [[package]]
 name = "byteorder-lite"
 version = "0.1.0"
@@ -71,6 +86,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "equivalent"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
+
 [[package]]
 name = "errno"
 version = "0.3.12"
@@ -112,6 +133,119 @@ dependencies = [
  "miniz_oxide",
 ]
 
+[[package]]
+name = "float_next_after"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8bf7cc16383c4b8d58b9905a8509f02926ce3058053c056376248d958c9df1e8"
+
+[[package]]
+name = "geo"
+version = "0.30.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4416397671d8997e9a3e7ad99714f4f00a22e9eaa9b966a5985d2194fc9e02e1"
+dependencies = [
+ "float_next_after",
+ "geo-types",
+ "geographiclib-rs",
+ "i_overlay",
+ "log",
+ "num-traits",
+ "proj",
+ "robust",
+ "rstar",
+ "serde",
+]
+
+[[package]]
+name = "geo-types"
+version = "0.7.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62ddb1950450d67efee2bbc5e429c68d052a822de3aad010d28b351fbb705224"
+dependencies = [
+ "approx",
+ "num-traits",
+ "rstar",
+ "serde",
+]
+
+[[package]]
+name = "geographiclib-rs"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f611040a2bb37eaa29a78a128d1e92a378a03e0b6e66ae27398d42b1ba9a7841"
+dependencies = [
+ "libm",
+]
+
+[[package]]
+name = "hash32"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47d60b12902ba28e2730cd37e95b8c9223af2808df9e902d4df49588d1470606"
+dependencies = [
+ "byteorder",
+]
+
+[[package]]
+name = "hashbrown"
+version = "0.15.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84b26c544d002229e640969970a2e74021aadf6e2f96372b9c58eff97de08eb3"
+
+[[package]]
+name = "heapless"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0bfb9eb618601c89945a70e254898da93b13be0388091d42117462b265bb3fad"
+dependencies = [
+ "hash32",
+ "stable_deref_trait",
+]
+
+[[package]]
+name = "i_float"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85df3a416829bb955fdc2416c7b73680c8dcea8d731f2c7aa23e1042fe1b8343"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "i_key_sort"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "347c253b4748a1a28baf94c9ce133b6b166f08573157e05afe718812bc599fcd"
+
+[[package]]
+name = "i_overlay"
+version = "2.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0542dfef184afdd42174a03dcc0625b6147fb73e1b974b1a08a2a42ac35cee49"
+dependencies = [
+ "i_float",
+ "i_key_sort",
+ "i_shape",
+ "i_tree",
+]
+
+[[package]]
+name = "i_shape"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0a38f5a42678726718ff924f6d4a0e79b129776aeed298f71de4ceedbd091bce"
+dependencies = [
+ "i_float",
+ "serde",
+]
+
+[[package]]
+name = "i_tree"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "155181bc97d770181cf9477da51218a19ee92a8e5be642e796661aee2b601139"
+
 [[package]]
 name = "image"
 version = "0.25.6"
@@ -124,12 +258,28 @@ dependencies = [
  "png",
 ]
 
+[[package]]
+name = "indexmap"
+version = "2.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cea70ddb795996207ad57735b50c5982d8844f38ba9ee5f1aedcfb708a2aa11e"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.172"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d750af042f7ef4f724306de029d18836c26c1765a54a6a3f094cbd23a7267ffa"
 
+[[package]]
+name = "libm"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f9fbbcab51052fe104eb5e5d351cf728d30a5be1fe14d9be8a3b097481fb97de"
+
 [[package]]
 name = "libredox"
 version = "0.1.3"
@@ -143,9 +293,9 @@ dependencies = [
 
 [[package]]
 name = "libsqlite3-sys"
-version = "0.32.0"
+version = "0.30.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fbb8270bb4060bd76c6e96f20c52d80620f1d82a3470885694e41e0f81ef6fe7"
+checksum = "2e99fb7a497b1e3339bc746195567ed8d3e24945ecd636e3619d20b9de9e9149"
 dependencies = [
  "pkg-config",
  "vcpkg",
@@ -166,6 +316,18 @@ version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cd945864f07fe9f5371a27ad7b52a172b4b499999f1d97574c9fa68373937e12"
 
+[[package]]
+name = "log"
+version = "0.4.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
+
+[[package]]
+name = "memchr"
+version = "2.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
+
 [[package]]
 name = "miniz_oxide"
 version = "0.8.8"
@@ -183,6 +345,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "071dfc062690e90b734c0b2273ce72ad0ffa95f0c74596bc250dcfd960262841"
 dependencies = [
  "autocfg",
+ "libm",
 ]
 
 [[package]]
@@ -215,10 +378,11 @@ dependencies = [
 
 [[package]]
 name = "proj"
-version = "0.30.0"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "58e0c01de214d7ea50ee6519969be9efdc6f0dc5ce6c64fbd4f054ea26d43ca4"
+checksum = "3939f58cd2f8e5f3bba7fb76b3854956d39b1b76cec4fe5f65481d18f9c92d22"
 dependencies = [
+ "geo-types",
  "libc",
  "num-traits",
  "proj-sys",
@@ -227,9 +391,9 @@ dependencies = [
 
 [[package]]
 name = "proj-sys"
-version = "0.26.0"
+version = "0.25.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a208129995443a4c475464c33308274be1578993b0ad266c9139188ed0dc7e91"
+checksum = "533a4ed2ab59f7605ecea26db7ed76572d30aed9d2a6a90738bc7f7e7b5a11d8"
 dependencies = [
  "cmake",
  "flate2",
@@ -257,6 +421,23 @@ dependencies = [
  "bitflags 2.9.1",
 ]
 
+[[package]]
+name = "robust"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4e27ee8bb91ca0adcf0ecb116293afa12d393f9c2b9b9cd54d33e8078fe19839"
+
+[[package]]
+name = "rstar"
+version = "0.12.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "421400d13ccfd26dfa5858199c30a5d76f9c54e0dba7575273025b43c5175dbb"
+dependencies = [
+ "heapless",
+ "num-traits",
+ "smallvec",
+]
+
 [[package]]
 name = "rustix"
 version = "1.0.7"
@@ -270,6 +451,35 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "serde"
+version = "1.0.219"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f0e2c6ed6606019b4e29e69dbaba95b11854410e5347d525002456dbbb786b6"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.219"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b0276cf7f2c73365f7157c8123c21cd9a50fbbd844757af28ca1f5925fc2a00"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "serde_spanned"
+version = "0.6.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87607cb1398ed59d48732e575a4c28a7a8ebf2454b964fe3f224f2afc07909e1"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "shlex"
 version = "1.3.0"
@@ -282,6 +492,18 @@ version = "0.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d66dc143e6b11c1eddc06d5c423cfc97062865baf299914ab64caa38182078fe"
 
+[[package]]
+name = "smallvec"
+version = "1.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8917285742e9f3e1683f0a9c4e6b57960b7314d0b08d30d1ecd426713ee2eee9"
+
+[[package]]
+name = "stable_deref_trait"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8f112729512f8e442d81f95a8a7ddf2b7c6b8a1a6f509a95864142b30cab2d3"
+
 [[package]]
 name = "syn"
 version = "2.0.101"
@@ -324,6 +546,47 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "toml"
+version = "0.8.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05ae329d1f08c4d17a59bed7ff5b5a769d062e64a62d34a3261b219e62cd5aae"
+dependencies = [
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_edit",
+]
+
+[[package]]
+name = "toml_datetime"
+version = "0.6.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3da5db5a963e24bc68be8b17b6fa82814bb22ee8660f192bb182771d498f09a3"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "toml_edit"
+version = "0.22.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "310068873db2c5b3e7659d2cc35d21855dbafa50d1ce336397c666e3cb08137e"
+dependencies = [
+ "indexmap",
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_write",
+ "winnow",
+]
+
+[[package]]
+name = "toml_write"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bfb942dfe1d8e29a7ee7fcbde5bd2b9a25fb89aa70caea2eba3bee836ff41076"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.18"
@@ -340,8 +603,11 @@ checksum = "accd4ea62f7bb7a82fe23066fb0957d48ef677f6eeb8215f372f52e48bb32426"
 name = "wetter"
 version = "0.1.0"
 dependencies = [
+ "geo",
  "image",
  "proj",
+ "serde",
+ "toml",
 ]
 
 [[package]]
@@ -417,6 +683,15 @@ version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
 
+[[package]]
+name = "winnow"
+version = "0.7.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c06928c8748d81b05c9be96aad92e1b6ff01833332f281e8cfca3be4b35fc9ec"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "xattr"
 version = "1.5.0"
diff --git a/Cargo.toml b/Cargo.toml
index e1b9644..3a90122 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,5 +4,8 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+geo = { version = "0.30.0", default-features = false, features = ["use-proj", "use-serde"] }
 image = { version = "0.25.6", default-features = false, features = ["png"] }
-proj = { version = "0.30.0", default-features = false }
+proj = "0.29.0"
+serde = { version = "1.0.219", features = ["derive"] }
+toml = "0.8.22"
diff --git a/src/config.rs b/src/config.rs
new file mode 100644
index 0000000..4851aa6
--- /dev/null
+++ b/src/config.rs
@@ -0,0 +1,22 @@
+use geo::Point;
+
+use serde::Deserialize;
+
+use std::collections::HashMap;
+
+use toml::de::Error;
+
+#[derive(Deserialize)]
+pub struct Config {
+    pois: HashMap<String, Point>,
+}
+
+impl Config {
+    pub fn from_toml(s: &str) -> Result<Self, Error> {
+        toml::from_str(s)
+    }
+
+    pub fn pois(&self) -> &HashMap<String, Point> {
+        &self.pois
+    }
+}
diff --git a/src/data/mod.rs b/src/data/mod.rs
index 95eee43..ca37c23 100644
--- a/src/data/mod.rs
+++ b/src/data/mod.rs
@@ -2,3 +2,4 @@ mod parser;
 mod rv;
 
 pub use rv::Rv;
+pub use rv::DATA_LEN as RV_DATA_LEN;
diff --git a/src/data/parser.rs b/src/data/parser.rs
index d91ba9f..f1c7a8a 100644
--- a/src/data/parser.rs
+++ b/src/data/parser.rs
@@ -1,9 +1,9 @@
+use std::fmt::{self, Display, Formatter};
 use std::io::{Error as IoError, Read, Seek};
 use std::num::ParseIntError;
 use std::slice;
 use std::str::{self, FromStr, Utf8Error};
 
-#[allow(dead_code)]
 #[derive(Debug)]
 pub enum ParseError {
     IoError(IoError),
@@ -12,6 +12,19 @@ pub enum ParseError {
     Utf8Error(Utf8Error),
 }
 
+impl Display for ParseError {
+    fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            ParseError::IoError(err) => err.fmt(fmt),
+            ParseError::ParseIntError(err) => err.fmt(fmt),
+            ParseError::Unexpected(actual, expected) => {
+                fmt.write_fmt(format_args!("Expected '{}', got '{}'", expected, actual))
+            }
+            ParseError::Utf8Error(err) => err.fmt(fmt),
+        }
+    }
+}
+
 pub struct Parser<R: Read + Seek> {
     r: R,
 }
diff --git a/src/data/rv.rs b/src/data/rv.rs
index 992c05d..27b7fd2 100644
--- a/src/data/rv.rs
+++ b/src/data/rv.rs
@@ -3,9 +3,11 @@ compile_error!("Only little-endian architectures are supported.");
 
 use crate::data::parser::{ParseError, Parser};
 
+use std::cmp::Ordering;
+use std::fmt::{self, Display, Formatter};
 use std::io::{Read, Seek};
 
-const DATA_LEN: usize = 1100 * 1200;
+pub const DATA_LEN: usize = 1100 * 1200;
 
 #[derive(Clone, Copy, Debug)]
 pub struct VersionMismatch {
@@ -13,7 +15,16 @@ pub struct VersionMismatch {
     pub expected: u8,
 }
 
-#[derive(Clone, Copy, Debug)]
+impl Display for VersionMismatch {
+    fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
+        fmt.write_fmt(format_args!(
+            "Expected data version {}, got {}",
+            self.expected, self.actual
+        ))
+    }
+}
+
+#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
 pub struct Datetime {
     pub year: u16,
     pub month: u8,
@@ -27,6 +38,7 @@ pub struct Rv {
     timestamp: Datetime,
     version: u8,
     precision: i8,
+    interval: u16,
     forecast: u16,
     data: Vec<u16>,
 }
@@ -68,7 +80,7 @@ impl Rv {
 
         parser.expect("INT")?;
 
-        let _interval = parser.parse_int::<u16, 4>()?;
+        let interval = parser.parse_int::<_, 4>()?;
 
         parser.expect("GP")?;
 
@@ -102,6 +114,7 @@ impl Rv {
             },
             version,
             precision,
+            interval,
             forecast,
             data,
         })
@@ -122,6 +135,10 @@ impl Rv {
         10_f64.powi(self.precision as i32)
     }
 
+    pub fn interval(&self) -> u16 {
+        self.interval
+    }
+
     pub fn instant(&self) -> (Datetime, u16) {
         (self.timestamp, self.forecast)
     }
@@ -130,3 +147,25 @@ impl Rv {
         &self.data[..]
     }
 }
+
+impl Eq for Rv {}
+
+impl Ord for Rv {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.timestamp
+            .cmp(&other.timestamp)
+            .then(self.forecast.cmp(&other.forecast))
+    }
+}
+
+impl PartialEq for Rv {
+    fn eq(&self, other: &Self) -> bool {
+        self.timestamp == other.timestamp && self.forecast == other.forecast
+    }
+}
+
+impl PartialOrd for Rv {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 588a336..fa235ba 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,14 +1,21 @@
+mod config;
 mod data;
 
-use data::Rv;
+use config::Config;
+
+use data::{Rv, RV_DATA_LEN};
 
 use image::imageops;
 use image::RgbaImage;
 
 use proj::Proj;
 
-use std::fs::File;
+use std::cmp::Reverse;
+use std::collections::BinaryHeap;
+use std::env;
+use std::fs::{self, File};
 use std::io::BufReader;
+use std::str;
 
 const PROJ_WGS84_DE1200: &'static str = "+proj=stere +lat_0=90 +lat_ts=60 +lon_0=10 +a=6378137 +b=6356752.3142451802 +no_defs +x_0=543196.83521776402 +y_0=3622588.8619310018";
 
@@ -21,17 +28,13 @@ enum Intensity {
     Unknown = 0xd0d0d080,
 }
 
-fn main() {
-    let rv = Rv::parse(BufReader::new(File::open("input").unwrap())).unwrap();
-    rv.expect_version(5).unwrap();
-
-    let mut data = Vec::with_capacity(1100 * 1200 * 4);
-
-    for v in rv.data() {
-        let intensity = if *v == 0x29c4 {
+impl Intensity {
+    fn from_rv_value(v: u16, scale: f64, interval: u16) -> Self {
+        if v == 0x29c4 {
             Intensity::Unknown
         } else {
-            let mm_per_h = *v as f64 * rv.scale() * 12.0; // 12 * 5 min intervals per hour
+            let mm_per_h = v as f64 * scale * (60.0 / interval as f64);
+
             if mm_per_h < 0.1 {
                 Intensity::None
             } else if mm_per_h < 5.0 {
@@ -41,23 +44,85 @@ fn main() {
             } else {
                 Intensity::Heavy
             }
-        };
+        }
+    }
+}
 
-        data.extend_from_slice(&(intensity as u32).to_be_bytes());
+fn main() -> Result<(), String> {
+    let config =
+        Config::from_toml(&fs::read_to_string("config.toml").map_err(|err| err.to_string())?)
+            .map_err(|err| err.to_string())?;
+
+    let mut heap = BinaryHeap::new();
+
+    for path in env::args().skip(1) {
+        let rv = Rv::parse(BufReader::new(
+            File::open(&path).map_err(|err| err.to_string())?,
+        ))
+        .map_err(|err| err.to_string())?;
+        rv.expect_version(5).map_err(|err| err.to_string())?;
+
+        heap.push(Reverse(rv));
     }
 
-    let mut img = RgbaImage::from_raw(1100, 1200, data).unwrap();
-    imageops::flip_vertical_in_place(&mut img);
-    img.save("rv.png").unwrap();
+    let Reverse(current) = heap.pop().ok_or("At least one file must be given")?;
 
-    let wgs84_to_de1200 = Proj::new(PROJ_WGS84_DE1200).unwrap();
-    println!(
-        "{:#?}",
-        wgs84_to_de1200
-            .project(
-                (1.463301510_f64.to_radians(), 55.86208711_f64.to_radians()),
-                false
-            )
-            .unwrap()
-    );
+    let (timestamp, offset) = current.instant();
+
+    if offset != 0 {
+        eprintln!(
+            "First file is expected to contain current situation, got forecast for +{} minutes",
+            offset
+        );
+    }
+
+    let mut img_data = Vec::with_capacity(RV_DATA_LEN * 4);
+
+    for v in current.data() {
+        let intensity = Intensity::from_rv_value(*v, current.scale(), current.interval());
+
+        img_data.extend_from_slice(&(intensity as u32).to_be_bytes());
+    }
+
+    let mut img = RgbaImage::from_raw(1100, 1200, img_data).unwrap();
+    imageops::flip_vertical_in_place(&mut img);
+    img.save(format!(
+        "rv_{}-{}-{}_{}:{}.png",
+        timestamp.year, timestamp.month, timestamp.day, timestamp.hour, timestamp.minute
+    ))
+    .map_err(|err| err.to_string())?;
+
+    let mut data = Vec::with_capacity(RV_DATA_LEN * heap.len());
+
+    while heap.len() > 0 {
+        let Reverse(forecast) = heap.pop().unwrap();
+        data.extend_from_slice(forecast.data());
+    }
+
+    let wgs84_to_de1200 = Proj::new(PROJ_WGS84_DE1200).map_err(|err| err.to_string())?;
+
+    for (name, poi) in config.pois() {
+        let (x, y) = (wgs84_to_de1200
+            .project(poi.to_radians(), false)
+            .map_err(|err| err.to_string())?
+            / 1000.0)
+            .x_y();
+
+        let (x, y) = (x.round() as usize, (1200 + y.round() as i64) as usize);
+        if !(0..1100).contains(&x) || !(0..1200).contains(&y) {
+            eprintln!("POI \"{}\" is out of range", name);
+            continue;
+        }
+
+        let v = current.data()[y * 1100 + x];
+        if v == 0x29c4 {
+            eprintln!("No value for POI \"{}\"", name);
+            continue;
+        }
+
+        let mm_per_h = v as f64 * current.scale() * (60.0 / current.interval() as f64);
+        println!("intensity{{poi=\"{}\"}} {}", name, mm_per_h);
+    }
+
+    Ok(())
 }
diff --git a/update.py b/update.py
new file mode 100755
index 0000000..1c86cbe
--- /dev/null
+++ b/update.py
@@ -0,0 +1,44 @@
+#!/usr/bin/env python3
+
+import subprocess
+import tarfile
+from datetime import UTC, datetime, timedelta
+from io import BytesIO
+from pathlib import Path
+from sys import exit, stderr, stdout
+
+import requests
+
+DATA_DIR = Path.cwd() / "data"
+DATA_DIR.mkdir(exist_ok=True)
+
+DOWNLOAD_URL = (
+    "https://opendata.dwd.de/weather/radar/composite/rv/DE1200_RV%y%m%d%H%M.tar.bz2"
+)
+
+now = datetime.now(UTC)
+now = now.replace(minute=now.minute // 5 * 5, second=0, microsecond=0)
+
+for dt in (now, now - timedelta(minutes=5)):
+    url = dt.strftime(DOWNLOAD_URL)
+    print(f"Attempting to download {url}", file=stderr)
+
+    try:
+        r = requests.get(url)
+        r.raise_for_status()
+        break
+    except requests.HTTPError:
+        print(f"Not Found: {url}")
+else:
+    exit()
+
+with tarfile.open(fileobj=BytesIO(r.content)) as tar:
+    tar.extractall(DATA_DIR, filter="data")
+    files = list(map(lambda n: DATA_DIR / n, tar.getnames()))
+
+subprocess.run(
+    [str(Path(__name__).resolve().parent / "target/release/wetter")] + files,
+    stdout=stdout,
+    stderr=stderr,
+    check=True,
+)